import org.junit.jupiter.api.Test import org.junit.jupiter.api.TestInstance import sim65.components.* import kotlin.test.assertEquals import kotlin.test.assertFalse import kotlin.test.assertTrue /* Unit test suite adapted from Py65 https://github.com/mnaberez/py65 Copyright (c) 2008-2018, Mike Naberezny and contributors. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ @TestInstance(TestInstance.Lifecycle.PER_METHOD) abstract class TestCommon6502 { // Tests common to 6502-based microprocessors val mpu = Cpu6502(true) // TODO make a 65C02 cpu as well and let the subclasses testsuites define the appropriate instance val memory = Ram(0, 0xffff) val bus = Bus() init { bus.add(mpu) bus.add(memory) mpu.reset() } companion object { // processor flags const val fNEGATIVE = 128 const val fOVERFLOW = 64 const val fUNUSED = 32 const val fBREAK = 16 const val fDECIMAL = 8 const val fINTERRUPT = 4 const val fZERO = 2 const val fCARRY = 1 } // test helpers fun writeMem(memory: MemMappedComponent, startAddress: Address, data: Iterable) { var addr = startAddress data.forEach { memory.write(addr++, it) } } // Reset @Test fun test_reset_sets_registers_to_initial_states() { mpu.reset() assertEquals(0xFF, mpu.SP) assertEquals(0, mpu.A) assertEquals(0, mpu.X) assertEquals(0, mpu.Y) assertEquals(Cpu6502.StatusRegister(C = false, Z = false, I = false, D = false, B = true, V = false, N = false), mpu.Status) } // ADC Absolute @Test fun test_adc_bcd_off_absolute_carry_clear_in_accumulator_zeroes() { mpu.A = 0 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) // assertEquals(0x10000, memory.size) memory[0xC000] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_absolute_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.Status.C = true // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_absolute_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0xFE mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_absolute_carry_clear_in_carry_set_out() { mpu.A = 0x02 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_absolute_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_absolute_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0xff mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_absolute_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_absolute_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0xff mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_absolute_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 // $0000 ADC $C000 writeMem(memory, 0x0000, listOf(0x6D, 0x00, 0xC0)) memory[0xC000] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) } // ADC Zero Page @Test fun test_adc_bcd_off_zp_carry_clear_in_accumulator_zeroes() { mpu.A = 0 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.Status.C = true // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_zp_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0xFE mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_carry_clear_in_carry_set_out() { mpu.A = 0x02 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0xff mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0xff mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_overflow_set_on_40_plus_40() { mpu.A = 0x40 mpu.Status.V = false // $0000 ADC $00B0 writeMem(memory, 0x0000, listOf(0x65, 0xB0)) memory[0x00B0] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // ADC Immediate } @Test fun test_adc_bcd_off_immediate_carry_clear_in_accumulator_zeroes() { mpu.A = 0 // $0000 ADC #$00 writeMem(memory, 0x0000, listOf(0x69, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_immediate_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.Status.C = true // $0000 ADC #$00 writeMem(memory, 0x0000, listOf(0x69, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_immediate_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 // $0000 ADC #$FE writeMem(memory, 0x0000, listOf(0x69, 0xFE)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_immediate_carry_clear_in_carry_set_out() { mpu.A = 0x02 // $0000 ADC #$FF writeMem(memory, 0x0000, listOf(0x69, 0xFF)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_immediate_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC #$01 writeMem(memory, 0x000, listOf(0x69, 0x01)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_immediate_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC #$FF writeMem(memory, 0x000, listOf(0x69, 0xff)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_immediate_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f // $0000 ADC #$01 writeMem(memory, 0x000, listOf(0x69, 0x01)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_immediate_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 // $0000 ADC #$FF writeMem(memory, 0x000, listOf(0x69, 0xff)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_immediate_overflow_set_on_40_plus_40() { mpu.A = 0x40 // $0000 ADC #$40 writeMem(memory, 0x0000, listOf(0x69, 0x40)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_on_immediate_79_plus_00_carry_set() { mpu.Status.D = true mpu.Status.C = true mpu.A = 0x79 // $0000 ADC #$00 writeMem(memory, 0x0000, listOf(0x69, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_on_immediate_6f_plus_00_carry_set() { mpu.Status.D = true mpu.Status.C = true mpu.A = 0x6f // $0000 ADC #$00 writeMem(memory, 0x0000, listOf(0x69, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x76, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.V) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_on_immediate_9c_plus_9d() { mpu.Status.D = true mpu.Status.C = false mpu.A = 0x9c // $0000 ADC #$9d // $0002 ADC #$9d writeMem(memory, 0x0000, listOf(0x69, 0x9d)) writeMem(memory, 0x0002, listOf(0x69, 0x9d)) mpu.step() assertEquals(0x9f, mpu.A) assertTrue(mpu.Status.C) mpu.step() assertEquals(0x0004, mpu.PC) assertEquals(0x93, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // ADC Absolute, X-Indexed } @Test fun test_adc_bcd_off_abs_x_carry_clear_in_accumulator_zeroes() { mpu.A = 0x00 mpu.X = 0x03 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_x_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.X = 0x03 mpu.Status.C = true // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_abs_x_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0xFE mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_x_carry_clear_in_carry_set_out() { mpu.A = 0x02 mpu.X = 0x03 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_x_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_x_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0xff mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_x_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_x_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0xff mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_x_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 mpu.X = 0x03 // $0000 ADC $C000,X writeMem(memory, 0x0000, listOf(0x7D, 0x00, 0xC0)) memory[0xC000 + mpu.X] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // ADC Absolute, Y-Indexed } @Test fun test_adc_bcd_off_abs_y_carry_clear_in_accumulator_zeroes() { mpu.A = 0x00 mpu.Y = 0x03 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_y_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.Y = 0x03 mpu.Status.C = true // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_abs_y_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 mpu.Y = 0x03 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0xFE mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_y_carry_clear_in_carry_set_out() { mpu.A = 0x02 mpu.Y = 0x03 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_abs_y_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_y_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_y_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_y_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_abs_y_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 mpu.Y = 0x03 // $0000 ADC $C000,Y writeMem(memory, 0x0000, listOf(0x79, 0x00, 0xC0)) memory[0xC000 + mpu.Y] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // ADC Zero Page, X-Indexed } @Test fun test_adc_bcd_off_zp_x_carry_clear_in_accumulator_zeroes() { mpu.A = 0x00 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_x_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.X = 0x03 mpu.Status.C = true // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_zp_x_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0xFE mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_x_carry_clear_in_carry_set_out() { mpu.A = 0x02 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_zp_x_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_x_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_x_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_x_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0xff mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_zp_x_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 mpu.X = 0x03 // $0000 ADC $0010,X writeMem(memory, 0x0000, listOf(0x75, 0x10)) memory[0x0010 + mpu.X] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // ADC Indirect, Indexed (X) } @Test fun test_adc_bcd_off_ind_indexed_carry_clear_in_accumulator_zeroes() { mpu.A = 0x00 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_ind_indexed_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.X = 0x03 mpu.Status.C = true // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_ind_indexed_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0xFE mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_ind_indexed_carry_clear_in_carry_set_out() { mpu.A = 0x02 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_ind_indexed_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_ind_indexed_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_ind_indexed_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_ind_indexed_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_ind_indexed_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 mpu.X = 0x03 // $0000 ADC ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x61, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // ADC Indexed, Indirect (Y) } @Test fun test_adc_bcd_off_indexed_ind_carry_clear_in_accumulator_zeroes() { mpu.A = 0x00 mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) } @Test fun test_adc_bcd_off_indexed_ind_carry_set_in_accumulator_zero() { mpu.A = 0 mpu.Y = 0x03 mpu.Status.C = true // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_adc_bcd_off_indexed_ind_carry_clear_in_no_carry_clear_out() { mpu.A = 0x01 mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFE mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.C) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_indexed_ind_carry_clear_in_carry_set_out() { mpu.A = 0x02 mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, mpu.A) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_adc_bcd_off_indexed_ind_overflow_clr_no_carry_01_plus_01() { mpu.Status.C = false mpu.A = 0x01 mpu.Y = 0x03 // $0000 $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_indexed_ind_overflow_clr_no_carry_01_plus_ff() { mpu.Status.C = false mpu.A = 0x01 mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertFalse(mpu.Status.V) } @Test fun test_adc_bcd_off_indexed_ind_overflow_set_no_carry_7f_plus_01() { mpu.Status.C = false mpu.A = 0x7f mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_indexed_ind_overflow_set_no_carry_80_plus_ff() { mpu.Status.C = false mpu.A = 0x80 mpu.Y = 0x03 // $0000 $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x7f, mpu.A) assertTrue(mpu.Status.V) } @Test fun test_adc_bcd_off_indexed_ind_overflow_set_on_40_plus_40() { mpu.Status.V = false mpu.A = 0x40 mpu.Y = 0x03 // $0000 ADC ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x71, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertTrue(mpu.Status.V) assertFalse(mpu.Status.Z) // AND (Absolute) } @Test fun test_and_absolute_all_zeros_setting_zero_flag() { mpu.A = 0xFF // $0000 AND $ABCD writeMem(memory, 0x0000, listOf(0x2D, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_absolute_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF // $0000 AND $ABCD writeMem(memory, 0x0000, listOf(0x2D, 0xCD, 0xAB)) memory[0xABCD] = 0xAA mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND (Absolute) } @Test fun test_and_zp_all_zeros_setting_zero_flag() { mpu.A = 0xFF // $0000 AND $0010 writeMem(memory, 0x0000, listOf(0x25, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_zp_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF // $0000 AND $0010 writeMem(memory, 0x0000, listOf(0x25, 0x10)) memory[0x0010] = 0xAA mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND (Immediate) } @Test fun test_and_immediate_all_zeros_setting_zero_flag() { mpu.A = 0xFF // $0000 AND #$00 writeMem(memory, 0x0000, listOf(0x29, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_immediate_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF // $0000 AND #$AA writeMem(memory, 0x0000, listOf(0x29, 0xAA)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND (Absolute, X-Indexed) } @Test fun test_and_abs_x_all_zeros_setting_zero_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND $ABCD,X writeMem(memory, 0x0000, listOf(0x3d, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_abs_x_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND $ABCD,X writeMem(memory, 0x0000, listOf(0x3d, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xAA mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND (Absolute, Y-Indexed) } @Test fun test_and_abs_y_all_zeros_setting_zero_flag() { mpu.A = 0xFF mpu.Y = 0x03 // $0000 AND $ABCD,X writeMem(memory, 0x0000, listOf(0x39, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_abs_y_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF mpu.Y = 0x03 // $0000 AND $ABCD,X writeMem(memory, 0x0000, listOf(0x39, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xAA mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND Indirect, Indexed (X) } @Test fun test_and_ind_indexed_x_all_zeros_setting_zero_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x21, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_ind_indexed_x_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x21, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0xAA mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND Indexed, Indirect (Y) } @Test fun test_and_indexed_ind_y_all_zeros_setting_zero_flag() { mpu.A = 0xFF mpu.Y = 0x03 // $0000 AND ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x31, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_indexed_ind_y_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF mpu.Y = 0x03 // $0000 AND ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x31, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xAA mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // AND Zero Page, X-Indexed } @Test fun test_and_zp_x_all_zeros_setting_zero_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND $0010,X writeMem(memory, 0x0000, listOf(0x35, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_and_zp_x_all_zeros_and_ones_setting_negative_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 AND $0010,X writeMem(memory, 0x0000, listOf(0x35, 0x10)) memory[0x0010 + mpu.X] = 0xAA mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ASL Accumulator } @Test fun test_asl_accumulator_sets_z_flag() { mpu.A = 0x00 // $0000 ASL A memory[0x0000] = 0x0A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_asl_accumulator_sets_n_flag() { mpu.A = 0x40 // $0000 ASL A memory[0x0000] = 0x0A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_asl_accumulator_shifts_out_zero() { mpu.A = 0x7F // $0000 ASL A memory[0x0000] = 0x0A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFE, mpu.A) assertFalse(mpu.Status.C) } @Test fun test_asl_accumulator_shifts_out_one() { mpu.A = 0xFF // $0000 ASL A memory[0x0000] = 0x0A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFE, mpu.A) assertTrue(mpu.Status.C) } @Test fun test_asl_accumulator_80_sets_z_flag() { mpu.A = 0x80 mpu.Status.Z = false // $0000 ASL A memory[0x0000] = 0x0A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) // ASL Absolute } @Test fun test_asl_absolute_sets_z_flag() { // $0000 ASL $ABCD writeMem(memory, 0x0000, listOf(0x0E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_asl_absolute_sets_n_flag() { // $0000 ASL $ABCD writeMem(memory, 0x0000, listOf(0x0E, 0xCD, 0xAB)) memory[0xABCD] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_asl_absolute_shifts_out_zero() { mpu.A = 0xAA // $0000 ASL $ABCD writeMem(memory, 0x0000, listOf(0x0E, 0xCD, 0xAB)) memory[0xABCD] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0xABCD]) assertFalse(mpu.Status.C) } @Test fun test_asl_absolute_shifts_out_one() { mpu.A = 0xAA // $0000 ASL $ABCD writeMem(memory, 0x0000, listOf(0x0E, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0xABCD]) assertTrue(mpu.Status.C) // ASL Zero Page } @Test fun test_asl_zp_sets_z_flag() { // $0000 ASL $0010 writeMem(memory, 0x0000, listOf(0x06, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_asl_zp_sets_n_flag() { // $0000 ASL $0010 writeMem(memory, 0x0000, listOf(0x06, 0x10)) memory[0x0010] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_asl_zp_shifts_out_zero() { mpu.A = 0xAA // $0000 ASL $0010 writeMem(memory, 0x0000, listOf(0x06, 0x10)) memory[0x0010] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0x0010]) assertFalse(mpu.Status.C) } @Test fun test_asl_zp_shifts_out_one() { mpu.A = 0xAA // $0000 ASL $0010 writeMem(memory, 0x0000, listOf(0x06, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0x0010]) assertTrue(mpu.Status.C) // ASL Absolute, X-Indexed } @Test fun test_asl_abs_x_indexed_sets_z_flag() { mpu.X = 0x03 // $0000 ASL $ABCD,X writeMem(memory, 0x0000, listOf(0x1E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_asl_abs_x_indexed_sets_n_flag() { mpu.X = 0x03 // $0000 ASL $ABCD,X writeMem(memory, 0x0000, listOf(0x1E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_asl_abs_x_indexed_shifts_out_zero() { mpu.A = 0xAA mpu.X = 0x03 // $0000 ASL $ABCD,X writeMem(memory, 0x0000, listOf(0x1E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_asl_abs_x_indexed_shifts_out_one() { mpu.A = 0xAA mpu.X = 0x03 // $0000 ASL $ABCD,X writeMem(memory, 0x0000, listOf(0x1E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.C) // ASL Zero Page, X-Indexed } @Test fun test_asl_zp_x_indexed_sets_z_flag() { mpu.X = 0x03 // $0000 ASL $0010,X writeMem(memory, 0x0000, listOf(0x16, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_asl_zp_x_indexed_sets_n_flag() { mpu.X = 0x03 // $0000 ASL $0010,X writeMem(memory, 0x0000, listOf(0x16, 0x10)) memory[0x0010 + mpu.X] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_asl_zp_x_indexed_shifts_out_zero() { mpu.X = 0x03 mpu.A = 0xAA // $0000 ASL $0010,X writeMem(memory, 0x0000, listOf(0x16, 0x10)) memory[0x0010 + mpu.X] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_asl_zp_x_indexed_shifts_out_one() { mpu.X = 0x03 mpu.A = 0xAA // $0000 ASL $0010,X writeMem(memory, 0x0000, listOf(0x16, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xAA, mpu.A) assertEquals(0xFE, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.C) // BCC } @Test fun test_bcc_carry_clear_branches_relative_forward() { mpu.Status.C = false // $0000 BCC +6 writeMem(memory, 0x0000, listOf(0x90, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bcc_carry_clear_branches_relative_backward() { mpu.Status.C = false mpu.PC = 0x0050 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 // $0000 BCC -6 writeMem(memory, 0x0050, listOf(0x90, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bcc_carry_set_does_not_branch() { mpu.Status.C = true // $0000 BCC +6 writeMem(memory, 0x0000, listOf(0x90, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BCS } @Test fun test_bcs_carry_set_branches_relative_forward() { mpu.Status.C = true // $0000 BCS +6 writeMem(memory, 0x0000, listOf(0xB0, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bcs_carry_set_branches_relative_backward() { mpu.Status.C = true mpu.PC = 0x0050 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 // $0000 BCS -6 writeMem(memory, 0x0050, listOf(0xB0, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bcs_carry_clear_does_not_branch() { mpu.Status.C = false // $0000 BCS +6 writeMem(memory, 0x0000, listOf(0xB0, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BEQ } @Test fun test_beq_zero_set_branches_relative_forward() { mpu.Status.Z = true // $0000 BEQ +6 writeMem(memory, 0x0000, listOf(0xF0, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_beq_zero_set_branches_relative_backward() { mpu.Status.Z = true mpu.PC = 0x0050 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 // $0000 BEQ -6 writeMem(memory, 0x0050, listOf(0xF0, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_beq_zero_clear_does_not_branch() { mpu.Status.Z = false // $0000 BEQ +6 writeMem(memory, 0x0000, listOf(0xF0, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BIT (Absolute) } @Test fun test_bit_abs_copies_bit_7_of_memory_to_n_flag_when_0() { mpu.Status.N = false // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0xFF mpu.A = 0xFF mpu.step() assertTrue(mpu.Status.N) } @Test fun test_bit_abs_copies_bit_7_of_memory_to_n_flag_when_1() { mpu.Status.N = true // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0x00 mpu.A = 0xFF mpu.step() assertFalse(mpu.Status.N) } @Test fun test_bit_abs_copies_bit_6_of_memory_to_v_flag_when_0() { mpu.Status.V = false // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0xFF mpu.A = 0xFF mpu.step() assertTrue(mpu.Status.V) } @Test fun test_bit_abs_copies_bit_6_of_memory_to_v_flag_when_1() { mpu.Status.V = true // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0x00 mpu.A = 0xFF mpu.step() assertFalse(mpu.Status.V) } @Test fun test_bit_abs_stores_result_of_and_in_z_preserves_a_when_1() { mpu.Status.Z = false // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0x00 mpu.A = 0x01 mpu.step() assertTrue(mpu.Status.Z) assertEquals(0x01, mpu.A) assertEquals(0x00, memory[0xFEED]) } @Test fun test_bit_abs_stores_result_of_and_when_nonzero_in_z_preserves_a() { mpu.Status.Z = true // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0x01 mpu.A = 0x01 mpu.step() assertFalse(mpu.Status.Z) // result of AND is non-zero assertEquals(0x01, mpu.A) assertEquals(0x01, memory[0xFEED]) } @Test fun test_bit_abs_stores_result_of_and_when_zero_in_z_preserves_a() { mpu.Status.Z = false // $0000 BIT $FEED writeMem(memory, 0x0000, listOf(0x2C, 0xED, 0xFE)) memory[0xFEED] = 0x00 mpu.A = 0x01 mpu.step() assertTrue(mpu.Status.Z) // result of AND is zero assertEquals(0x01, mpu.A) assertEquals(0x00, memory[0xFEED]) // BIT (Zero Page) } @Test fun test_bit_zp_copies_bit_7_of_memory_to_n_flag_when_0() { mpu.Status.N = false // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0xFF mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertTrue(mpu.Status.N) } @Test fun test_bit_zp_copies_bit_7_of_memory_to_n_flag_when_1() { mpu.Status.N = true // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0x00 mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertFalse(mpu.Status.N) } @Test fun test_bit_zp_copies_bit_6_of_memory_to_v_flag_when_0() { mpu.Status.V = false // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0xFF mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertTrue(mpu.Status.V) } @Test fun test_bit_zp_copies_bit_6_of_memory_to_v_flag_when_1() { mpu.Status.V = true // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0x00 mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertFalse(mpu.Status.V) } @Test fun test_bit_zp_stores_result_of_and_in_z_preserves_a_when_1() { mpu.Status.Z = false // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0x00 mpu.A = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertTrue(mpu.Status.Z) assertEquals(0x01, mpu.A) assertEquals(0x00, memory[0x0010]) } @Test fun test_bit_zp_stores_result_of_and_when_nonzero_in_z_preserves_a() { mpu.Status.Z = true // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0x01 mpu.A = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertFalse(mpu.Status.Z) // result of AND is non-zero assertEquals(0x01, mpu.A) assertEquals(0x01, memory[0x0010]) } @Test fun test_bit_zp_stores_result_of_and_when_zero_in_z_preserves_a() { mpu.Status.Z = false // $0000 BIT $0010 writeMem(memory, 0x0000, listOf(0x24, 0x10)) memory[0x0010] = 0x00 mpu.A = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(3, mpu.totalCycles) assertTrue(mpu.Status.Z) // result of AND is zero assertEquals(0x01, mpu.A) assertEquals(0x00, memory[0x0010]) // BMI } @Test fun test_bmi_negative_set_branches_relative_forward() { mpu.Status.N = true // $0000 BMI +06 writeMem(memory, 0x0000, listOf(0x30, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bmi_negative_set_branches_relative_backward() { mpu.Status.N = true mpu.PC = 0x0050 // $0000 BMI -6 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 writeMem(memory, 0x0050, listOf(0x30, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bmi_negative_clear_does_not_branch() { mpu.Status.N = false // $0000 BEQ +6 writeMem(memory, 0x0000, listOf(0x30, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BNE } @Test fun test_bne_zero_clear_branches_relative_forward() { mpu.Status.Z = false // $0000 BNE +6 writeMem(memory, 0x0000, listOf(0xD0, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bne_zero_clear_branches_relative_backward() { mpu.Status.Z = false mpu.PC = 0x0050 // $0050 BNE -6 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 writeMem(memory, 0x0050, listOf(0xD0, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bne_zero_set_does_not_branch() { mpu.Status.Z = true // $0000 BNE +6 writeMem(memory, 0x0000, listOf(0xD0, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BPL } @Test fun test_bpl_negative_clear_branches_relative_forward() { mpu.Status.N = false // $0000 BPL +06 writeMem(memory, 0x0000, listOf(0x10, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bpl_negative_clear_branches_relative_backward() { mpu.Status.N = false mpu.PC = 0x0050 // $0050 BPL -6 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 writeMem(memory, 0x0050, listOf(0x10, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bpl_negative_set_does_not_branch() { mpu.Status.N = true // $0000 BPL +6 writeMem(memory, 0x0000, listOf(0x10, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) // BRK } @Test fun test_brk_pushes_pc_plus_2_and_status_then_sets_pc_to_irq_vector() { writeMem(memory, 0xFFFE, listOf(0xCD, 0xAB)) // $C000 BRK memory[0xC000] = 0x00 mpu.PC = 0xC000 mpu.step() assertEquals(0xABCD, mpu.PC) assertEquals(0xC0, memory[0x1FF]) // PCH assertEquals(0x02, memory[0x1FE]) // PCL assertEquals(fBREAK or fUNUSED, memory[0x1FD].toInt()) // Status assertEquals(0xFC, mpu.SP) assertEquals(fBREAK or fUNUSED or fINTERRUPT, mpu.Status.asByte().toInt()) } // BVC @Test fun test_bvc_overflow_clear_branches_relative_forward() { mpu.Status.V = false // $0000 BVC +6 writeMem(memory, 0x0000, listOf(0x50, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bvc_overflow_clear_branches_relative_backward() { mpu.Status.V = false mpu.PC = 0x0050 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 // $0050 BVC -6 writeMem(memory, 0x0050, listOf(0x50, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bvc_overflow_set_does_not_branch() { mpu.Status.V = true // $0000 BVC +6 writeMem(memory, 0x0000, listOf(0x50, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) } // BVS @Test fun test_bvs_overflow_set_branches_relative_forward() { mpu.Status.V = true // $0000 BVS +6 writeMem(memory, 0x0000, listOf(0x70, 0x06)) mpu.step() assertEquals(0x0002 + 0x06, mpu.PC) } @Test fun test_bvs_overflow_set_branches_relative_backward() { mpu.Status.V = true mpu.PC = 0x0050 val rel = (0x06 xor 0xFF + 1) // two's complement of 6 // $0050 BVS -6 writeMem(memory, 0x0050, listOf(0x70, rel.toShort())) mpu.step() assertEquals(0x0052 + rel, mpu.PC) } @Test fun test_bvs_overflow_clear_does_not_branch() { mpu.Status.V = false // $0000 BVS +6 writeMem(memory, 0x0000, listOf(0x70, 0x06)) mpu.step() assertEquals(0x0002, mpu.PC) } // CLC @Test fun test_clc_clears_carry_flag() { mpu.Status.C = true // $0000 CLC memory[0x0000] = 0x18 mpu.step() assertEquals(0x0001, mpu.PC) assertFalse(mpu.Status.C) } // CLD @Test fun test_cld_clears_decimal_flag() { mpu.Status.D = true // $0000 CLD memory[0x0000] = 0xD8 mpu.step() assertEquals(0x0001, mpu.PC) assertFalse(mpu.Status.D) } // CLI @Test fun test_cli_clears_interrupt_mask_flag() { mpu.Status.I = true // $0000 CLI memory[0x0000] = 0x58 mpu.step() assertEquals(0x0001, mpu.PC) assertFalse(mpu.Status.I) } // CLV @Test fun test_clv_clears_overflow_flag() { mpu.Status.V = true // $0000 CLV memory[0x0000] = 0xB8 mpu.step() assertEquals(0x0001, mpu.PC) assertFalse(mpu.Status.V) } // Compare instructions // See http://6502.org/tutorials/compare_instructions.html // and http://www.6502.org/tutorials/compare_beyond.html // Cheat sheet: // - Comparison is actually subtraction "register - memory" // - Z contains equality result (1 equal, 0 not equal) // - C contains result of unsigned comparison (0 if A=m) // - N holds MSB of subtraction result (*NOT* of signed subtraction) // - V is not affected by comparison // - D has no effect on comparison // CMP Immediate @Test fun test_cmp_imm_sets_zero_carry_clears_neg_flags_if_equal() { // Comparison: A == m // $0000 CMP #10 , A will be 10 writeMem(memory, 0x0000, listOf(0xC9, 10)) mpu.A = 10 mpu.step() assertEquals(0x0002, mpu.PC) assertFalse(mpu.Status.N) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) } @Test fun test_cmp_imm_clears_zero_carry_takes_neg_if_less_unsigned() { // Comparison: A < m (unsigned) // $0000 CMP #10 , A will be 1 writeMem(memory, 0x0000, listOf(0xC9, 10)) mpu.A = 1 mpu.step() assertEquals(0x0002, mpu.PC) assertTrue(mpu.Status.N) // 0x01-0x0A=0xF7 assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_cmp_imm_clears_zero_sets_carry_takes_neg_if_less_signed() { // Comparison: A < #nn (signed), A negative // $0000 CMP #1, A will be -1 (0xFF) writeMem(memory, 0x0000, listOf(0xC9, 1)) mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertTrue(mpu.Status.N) // 0xFF-0x01=0xFE assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // A>m unsigned } @Test fun test_cmp_imm_clears_zero_carry_takes_neg_if_less_signed_nega() { // Comparison: A < m (signed), A and m both negative // $0000 CMP #0xFF (-1), A will be -2 (0xFE) writeMem(memory, 0x0000, listOf(0xC9, 0xFF)) mpu.A = 0xFE mpu.step() assertEquals(0x0002, mpu.PC) assertTrue(mpu.Status.N) // 0xFE-0xFF=0xFF assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) // A m (unsigned) // $0000 CMP #1 , A will be 10 writeMem(memory, 0x0000, listOf(0xC9, 1)) mpu.A = 10 mpu.step() assertEquals(0x0002, mpu.PC) assertFalse(mpu.Status.N) // 0x0A-0x01 = 0x09 assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // A>m unsigned } @Test fun test_cmp_imm_clears_zero_carry_takes_neg_if_more_signed() { // Comparison: A > m (signed), memory negative // $0000 CMP #$FF (-1), A will be 2 writeMem(memory, 0x0000, listOf(0xC9, 0xFF)) mpu.A = 2 mpu.step() assertEquals(0x0002, mpu.PC) assertFalse(mpu.Status.N) // 0x02-0xFF=0x01 assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) // A m (signed), A and m both negative // $0000 CMP #$FE (-2), A will be -1 (0xFF) writeMem(memory, 0x0000, listOf(0xC9, 0xFE)) mpu.A = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertFalse(mpu.Status.N) // 0xFF-0xFE=0x01 assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // A>m unsigned } // CPX Immediate @Test fun test_cpx_imm_sets_zero_carry_clears_neg_flags_if_equal() { // Comparison: X == m // $0000 CPX #$20 writeMem(memory, 0x0000, listOf(0xE0, 0x20)) mpu.X = 0x20 mpu.step() assertEquals(0x0002, mpu.PC) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } // CPY Immediate @Test fun test_cpy_imm_sets_zero_carry_clears_neg_flags_if_equal() { // Comparison: Y == m // $0000 CPY #$30 writeMem(memory, 0x0000, listOf(0xC0, 0x30)) mpu.Y = 0x30 mpu.step() assertEquals(0x0002, mpu.PC) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } // DEC Absolute @Test fun test_dec_abs_decrements_memory() { // $0000 DEC 0xABCD writeMem(memory, 0x0000, listOf(0xCE, 0xCD, 0xAB)) memory[0xABCD] = 0x10 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x0F, memory[0xABCD]) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dec_abs_below_00_rolls_over_and_sets_negative_flag() { // $0000 DEC 0xABCD writeMem(memory, 0x0000, listOf(0xCE, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_dec_abs_sets_zero_flag_when_decrementing_to_zero() { // $0000 DEC 0xABCD writeMem(memory, 0x0000, listOf(0xCE, 0xCD, 0xAB)) memory[0xABCD] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } // DEC Zero Page @Test fun test_dec_zp_decrements_memory() { // $0000 DEC 0x0010 writeMem(memory, 0x0000, listOf(0xC6, 0x10)) memory[0x0010] = 0x10 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x0F, memory[0x0010]) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dec_zp_below_00_rolls_over_and_sets_negative_flag() { // $0000 DEC 0x0010 writeMem(memory, 0x0000, listOf(0xC6, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_dec_zp_sets_zero_flag_when_decrementing_to_zero() { // $0000 DEC 0x0010 writeMem(memory, 0x0000, listOf(0xC6, 0x10)) memory[0x0010] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } // DEC Absolute, X-Indexed @Test fun test_dec_abs_x_decrements_memory() { // $0000 DEC 0xABCD,X writeMem(memory, 0x0000, listOf(0xDE, 0xCD, 0xAB)) mpu.X = 0x03 memory[0xABCD + mpu.X] = 0x10 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x0F, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dec_abs_x_below_00_rolls_over_and_sets_negative_flag() { // $0000 DEC 0xABCD,X writeMem(memory, 0x0000, listOf(0xDE, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_dec_abs_x_sets_zero_flag_when_decrementing_to_zero() { // $0000 DEC 0xABCD,X writeMem(memory, 0x0000, listOf(0xDE, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } // DEC Zero Page, X-Indexed @Test fun test_dec_zp_x_decrements_memory() { // $0000 DEC 0x0010,X writeMem(memory, 0x0000, listOf(0xD6, 0x10)) mpu.X = 0x03 memory[0x0010 + mpu.X] = 0x10 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x0F, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dec_zp_x_below_00_rolls_over_and_sets_negative_flag() { // $0000 DEC 0x0010,X writeMem(memory, 0x0000, listOf(0xD6, 0x10)) mpu.X = 0x03 memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_dec_zp_x_sets_zero_flag_when_decrementing_to_zero() { // $0000 DEC 0x0010,X writeMem(memory, 0x0000, listOf(0xD6, 0x10)) mpu.X = 0x03 memory[0x0010 + mpu.X] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } // DEX @Test fun test_dex_decrements_x() { mpu.X = 0x10 // $0000 DEX memory[0x0000] = 0xCA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x0F, mpu.X) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dex_below_00_rolls_over_and_sets_negative_flag() { mpu.X = 0x00 // $0000 DEX memory[0x0000] = 0xCA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFF, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dex_sets_zero_flag_when_decrementing_to_zero() { mpu.X = 0x01 // $0000 DEX memory[0x0000] = 0xCA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } // DEY @Test fun test_dey_decrements_y() { mpu.Y = 0x10 // $0000 DEY memory[0x0000] = 0x88 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x0F, mpu.Y) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_dey_below_00_rolls_over_and_sets_negative_flag() { mpu.Y = 0x00 // $0000 DEY memory[0x0000] = 0x88 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFF, mpu.Y) assertTrue(mpu.Status.N) } @Test fun test_dey_sets_zero_flag_when_decrementing_to_zero() { mpu.Y = 0x01 // $0000 DEY memory[0x0000] = 0x88 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) } // EOR Absolute @Test fun test_eor_absolute_flips_bits_over_setting_z_flag() { mpu.A = 0xFF writeMem(memory, 0x0000, listOf(0x4D, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0xABCD]) assertTrue(mpu.Status.Z) } @Test fun test_eor_absolute_flips_bits_over_setting_n_flag() { mpu.A = 0x00 writeMem(memory, 0x0000, listOf(0x4D, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0xABCD]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Zero Page } @Test fun test_eor_zp_flips_bits_over_setting_z_flag() { mpu.A = 0xFF writeMem(memory, 0x0000, listOf(0x45, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0x0010]) assertTrue(mpu.Status.Z) } @Test fun test_eor_zp_flips_bits_over_setting_n_flag() { mpu.A = 0x00 writeMem(memory, 0x0000, listOf(0x45, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0x0010]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Immediate } @Test fun test_eor_immediate_flips_bits_over_setting_z_flag() { mpu.A = 0xFF writeMem(memory, 0x0000, listOf(0x49, 0xFF)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_eor_immediate_flips_bits_over_setting_n_flag() { mpu.A = 0x00 writeMem(memory, 0x0000, listOf(0x49, 0xFF)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Absolute, X-Indexed } @Test fun test_eor_abs_x_indexed_flips_bits_over_setting_z_flag() { mpu.A = 0xFF mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x5D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) } @Test fun test_eor_abs_x_indexed_flips_bits_over_setting_n_flag() { mpu.A = 0x00 mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x5D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Absolute, Y-Indexed } @Test fun test_eor_abs_y_indexed_flips_bits_over_setting_z_flag() { mpu.A = 0xFF mpu.Y = 0x03 writeMem(memory, 0x0000, listOf(0x59, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.Y]) assertTrue(mpu.Status.Z) } @Test fun test_eor_abs_y_indexed_flips_bits_over_setting_n_flag() { mpu.A = 0x00 mpu.Y = 0x03 writeMem(memory, 0x0000, listOf(0x59, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.Y]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Indirect, Indexed (X) } @Test fun test_eor_ind_indexed_x_flips_bits_over_setting_z_flag() { mpu.A = 0xFF mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x41, 0x10)) // => EOR listOf($0010,X) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) // => Vector to $ABCD memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0xABCD]) assertTrue(mpu.Status.Z) } @Test fun test_eor_ind_indexed_x_flips_bits_over_setting_n_flag() { mpu.A = 0x00 mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x41, 0x10)) // => EOR listOf($0010,X) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) // => Vector to $ABCD memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0xABCD]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Indexed, Indirect (Y) } @Test fun test_eor_indexed_ind_y_flips_bits_over_setting_z_flag() { mpu.A = 0xFF mpu.Y = 0x03 writeMem(memory, 0x0000, listOf(0x51, 0x10)) // => EOR listOf($0010),Y writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) // => Vector to $ABCD memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.Y]) assertTrue(mpu.Status.Z) } @Test fun test_eor_indexed_ind_y_flips_bits_over_setting_n_flag() { mpu.A = 0x00 mpu.Y = 0x03 writeMem(memory, 0x0000, listOf(0x51, 0x10)) // => EOR listOf($0010),Y writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) // => Vector to $ABCD memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0xABCD + mpu.Y]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // EOR Zero Page, X-Indexed } @Test fun test_eor_zp_x_indexed_flips_bits_over_setting_z_flag() { mpu.A = 0xFF mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x55, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0xFF, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) } @Test fun test_eor_zp_x_indexed_flips_bits_over_setting_n_flag() { mpu.A = 0x00 mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x55, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, mpu.A) assertEquals(0xFF, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // INC Absolute } @Test fun test_inc_abs_increments_memory() { writeMem(memory, 0x0000, listOf(0xEE, 0xCD, 0xAB)) memory[0xABCD] = 0x09 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x0A, memory[0xABCD]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_abs_increments_memory_rolls_over_and_sets_zero_flag() { writeMem(memory, 0x0000, listOf(0xEE, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_abs_sets_negative_flag_when_incrementing_above_7F() { writeMem(memory, 0x0000, listOf(0xEE, 0xCD, 0xAB)) memory[0xABCD] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) // INC Zero Page } @Test fun test_inc_zp_increments_memory() { writeMem(memory, 0x0000, listOf(0xE6, 0x10)) memory[0x0010] = 0x09 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x0A, memory[0x0010]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_zp_increments_memory_rolls_over_and_sets_zero_flag() { writeMem(memory, 0x0000, listOf(0xE6, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_zp_sets_negative_flag_when_incrementing_above_7F() { writeMem(memory, 0x0000, listOf(0xE6, 0x10)) memory[0x0010] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) // INC Absolute, X-Indexed } @Test fun test_inc_abs_x_increments_memory() { writeMem(memory, 0x0000, listOf(0xFE, 0xCD, 0xAB)) mpu.X = 0x03 memory[0xABCD + mpu.X] = 0x09 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x0A, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_abs_x_increments_memory_rolls_over_and_sets_zero_flag() { writeMem(memory, 0x0000, listOf(0xFE, 0xCD, 0xAB)) mpu.X = 0x03 memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_abs_x_sets_negative_flag_when_incrementing_above_7F() { writeMem(memory, 0x0000, listOf(0xFE, 0xCD, 0xAB)) mpu.X = 0x03 memory[0xABCD + mpu.X] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) // INC Zero Page, X-Indexed } @Test fun test_inc_zp_x_increments_memory() { writeMem(memory, 0x0000, listOf(0xF6, 0x10)) mpu.X = 0x03 memory[0x0010 + mpu.X] = 0x09 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x0A, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_zp_x_increments_memory_rolls_over_and_sets_zero_flag() { writeMem(memory, 0x0000, listOf(0xF6, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inc_zp_x_sets_negative_flag_when_incrementing_above_7F() { writeMem(memory, 0x0000, listOf(0xF6, 0x10)) memory[0x0010 + mpu.X] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) // INX } @Test fun test_inx_increments_x() { mpu.X = 0x09 memory[0x0000] = 0xE8 // => INX mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x0A, mpu.X) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_inx_above_FF_rolls_over_and_sets_zero_flag() { mpu.X = 0xFF memory[0x0000] = 0xE8 // => INX mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) } @Test fun test_inx_sets_negative_flag_when_incrementing_above_7F() { mpu.X = 0x7f memory[0x0000] = 0xE8 // => INX mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) // INY } @Test fun test_iny_increments_y() { mpu.Y = 0x09 memory[0x0000] = 0xC8 // => INY mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x0A, mpu.Y) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_iny_above_FF_rolls_over_and_sets_zero_flag() { mpu.Y = 0xFF memory[0x0000] = 0xC8 // => INY mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) } @Test fun test_iny_sets_negative_flag_when_incrementing_above_7F() { mpu.Y = 0x7f memory[0x0000] = 0xC8 // => INY mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) // JMP Absolute } @Test fun test_jmp_abs_jumps_to_absolute_address() { // $0000 JMP $ABCD writeMem(memory, 0x0000, listOf(0x4C, 0xCD, 0xAB)) mpu.step() assertEquals(0xABCD, mpu.PC) // JMP Indirect } @Test fun test_jmp_ind_jumps_to_indirect_address() { // $0000 JMP ($ABCD) writeMem(memory, 0x0000, listOf(0x6C, 0x00, 0x02)) writeMem(memory, 0x0200, listOf(0xCD, 0xAB)) mpu.step() assertEquals(0xABCD, mpu.PC) // JSR } @Test fun test_jsr_pushes_pc_plus_2_and_sets_pc() { // $C000 JSR $FFD2 writeMem(memory, 0xC000, listOf(0x20, 0xD2, 0xFF)) mpu.PC = 0xC000 mpu.step() assertEquals(0xFFD2, mpu.PC) assertEquals(0xFD, mpu.SP) assertEquals(0xC0, memory[0x01FF]) // PCH assertEquals(0x02, memory[0x01FE]) // PCL+2 // LDA Absolute } @Test fun test_lda_absolute_loads_a_sets_n_flag() { mpu.A = 0x00 // $0000 LDA $ABCD writeMem(memory, 0x0000, listOf(0xAD, 0xCD, 0xAB)) memory[0xABCD] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_absolute_loads_a_sets_z_flag() { mpu.A = 0xFF // $0000 LDA $ABCD writeMem(memory, 0x0000, listOf(0xAD, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDA Zero Page } @Test fun test_lda_zp_loads_a_sets_n_flag() { mpu.A = 0x00 // $0000 LDA $0010 writeMem(memory, 0x0000, listOf(0xA5, 0x10)) memory[0x0010] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_zp_loads_a_sets_z_flag() { mpu.A = 0xFF // $0000 LDA $0010 writeMem(memory, 0x0000, listOf(0xA5, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDA Immediate } @Test fun test_lda_immediate_loads_a_sets_n_flag() { mpu.A = 0x00 // $0000 LDA #$80 writeMem(memory, 0x0000, listOf(0xA9, 0x80)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_immediate_loads_a_sets_z_flag() { mpu.A = 0xFF // $0000 LDA #$00 writeMem(memory, 0x0000, listOf(0xA9, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDA Absolute, X-Indexed } @Test fun test_lda_abs_x_indexed_loads_a_sets_n_flag() { mpu.A = 0x00 mpu.X = 0x03 // $0000 LDA $ABCD,X writeMem(memory, 0x0000, listOf(0xBD, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_abs_x_indexed_loads_a_sets_z_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 LDA $ABCD,X writeMem(memory, 0x0000, listOf(0xBD, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_lda_abs_x_indexed_does_not_page_wrap() { mpu.A = 0 mpu.X = 0xFF // $0000 LDA $0080,X writeMem(memory, 0x0000, listOf(0xBD, 0x80, 0x00)) memory[0x0080 + mpu.X] = 0x42 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x42, mpu.A) // LDA Absolute, Y-Indexed } @Test fun test_lda_abs_y_indexed_loads_a_sets_n_flag() { mpu.A = 0x00 mpu.Y = 0x03 // $0000 LDA $ABCD,Y writeMem(memory, 0x0000, listOf(0xB9, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_abs_y_indexed_loads_a_sets_z_flag() { mpu.A = 0xFF mpu.Y = 0x03 // $0000 LDA $ABCD,Y writeMem(memory, 0x0000, listOf(0xB9, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_lda_abs_y_indexed_does_not_page_wrap() { mpu.A = 0 mpu.Y = 0xFF // $0000 LDA $0080,X writeMem(memory, 0x0000, listOf(0xB9, 0x80, 0x00)) memory[0x0080 + mpu.Y] = 0x42 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x42, mpu.A) // LDA Indirect, Indexed (X) } @Test fun test_lda_ind_indexed_x_loads_a_sets_n_flag() { mpu.A = 0x00 mpu.X = 0x03 // $0000 LDA ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0xA1, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_ind_indexed_x_loads_a_sets_z_flag() { mpu.A = 0x00 mpu.X = 0x03 // $0000 LDA ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0xA1, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDA Indexed, Indirect (Y) } @Test fun test_lda_indexed_ind_y_loads_a_sets_n_flag() { mpu.A = 0x00 mpu.Y = 0x03 // $0000 LDA ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0xB1, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_indexed_ind_y_loads_a_sets_z_flag() { mpu.A = 0x00 mpu.Y = 0x03 // $0000 LDA ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0xB1, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDA Zero Page, X-Indexed } @Test fun test_lda_zp_x_indexed_loads_a_sets_n_flag() { mpu.A = 0x00 mpu.X = 0x03 // $0000 LDA $10,X writeMem(memory, 0x0000, listOf(0xB5, 0x10)) memory[0x0010 + mpu.X] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_lda_zp_x_indexed_loads_a_sets_z_flag() { mpu.A = 0xFF mpu.X = 0x03 // $0000 LDA $10,X writeMem(memory, 0x0000, listOf(0xB5, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDX Absolute } @Test fun test_ldx_absolute_loads_x_sets_n_flag() { mpu.X = 0x00 // $0000 LDX $ABCD writeMem(memory, 0x0000, listOf(0xAE, 0xCD, 0xAB)) memory[0xABCD] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldx_absolute_loads_x_sets_z_flag() { mpu.X = 0xFF // $0000 LDX $ABCD writeMem(memory, 0x0000, listOf(0xAE, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDX Zero Page } @Test fun test_ldx_zp_loads_x_sets_n_flag() { mpu.X = 0x00 // $0000 LDX $0010 writeMem(memory, 0x0000, listOf(0xA6, 0x10)) memory[0x0010] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldx_zp_loads_x_sets_z_flag() { mpu.X = 0xFF // $0000 LDX $0010 writeMem(memory, 0x0000, listOf(0xA6, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDX Immediate } @Test fun test_ldx_immediate_loads_x_sets_n_flag() { mpu.X = 0x00 // $0000 LDX #$80 writeMem(memory, 0x0000, listOf(0xA2, 0x80)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldx_immediate_loads_x_sets_z_flag() { mpu.X = 0xFF // $0000 LDX #$00 writeMem(memory, 0x0000, listOf(0xA2, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDX Absolute, Y-Indexed } @Test fun test_ldx_abs_y_indexed_loads_x_sets_n_flag() { mpu.X = 0x00 mpu.Y = 0x03 // $0000 LDX $ABCD,Y writeMem(memory, 0x0000, listOf(0xBE, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldx_abs_y_indexed_loads_x_sets_z_flag() { mpu.X = 0xFF mpu.Y = 0x03 // $0000 LDX $ABCD,Y writeMem(memory, 0x0000, listOf(0xBE, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDX Zero Page, Y-Indexed } @Test fun test_ldx_zp_y_indexed_loads_x_sets_n_flag() { mpu.X = 0x00 mpu.Y = 0x03 // $0000 LDX $0010,Y writeMem(memory, 0x0000, listOf(0xB6, 0x10)) memory[0x0010 + mpu.Y] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldx_zp_y_indexed_loads_x_sets_z_flag() { mpu.X = 0xFF mpu.Y = 0x03 // $0000 LDX $0010,Y writeMem(memory, 0x0000, listOf(0xB6, 0x10)) memory[0x0010 + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDY Absolute } @Test fun test_ldy_absolute_loads_y_sets_n_flag() { mpu.Y = 0x00 // $0000 LDY $ABCD writeMem(memory, 0x0000, listOf(0xAC, 0xCD, 0xAB)) memory[0xABCD] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldy_absolute_loads_y_sets_z_flag() { mpu.Y = 0xFF // $0000 LDY $ABCD writeMem(memory, 0x0000, listOf(0xAC, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDY Zero Page } @Test fun test_ldy_zp_loads_y_sets_n_flag() { mpu.Y = 0x00 // $0000 LDY $0010 writeMem(memory, 0x0000, listOf(0xA4, 0x10)) memory[0x0010] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldy_zp_loads_y_sets_z_flag() { mpu.Y = 0xFF // $0000 LDY $0010 writeMem(memory, 0x0000, listOf(0xA4, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDY Immediate } @Test fun test_ldy_immediate_loads_y_sets_n_flag() { mpu.Y = 0x00 // $0000 LDY #$80 writeMem(memory, 0x0000, listOf(0xA0, 0x80)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldy_immediate_loads_y_sets_z_flag() { mpu.Y = 0xFF // $0000 LDY #$00 writeMem(memory, 0x0000, listOf(0xA0, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDY Absolute, X-Indexed } @Test fun test_ldy_abs_x_indexed_loads_x_sets_n_flag() { mpu.Y = 0x00 mpu.X = 0x03 // $0000 LDY $ABCD,X writeMem(memory, 0x0000, listOf(0xBC, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldy_abs_x_indexed_loads_x_sets_z_flag() { mpu.Y = 0xFF mpu.X = 0x03 // $0000 LDY $ABCD,X writeMem(memory, 0x0000, listOf(0xBC, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LDY Zero Page, X-Indexed } @Test fun test_ldy_zp_x_indexed_loads_x_sets_n_flag() { mpu.Y = 0x00 mpu.X = 0x03 // $0000 LDY $0010,X writeMem(memory, 0x0000, listOf(0xB4, 0x10)) memory[0x0010 + mpu.X] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_ldy_zp_x_indexed_loads_x_sets_z_flag() { mpu.Y = 0xFF mpu.X = 0x03 // $0000 LDY $0010,X writeMem(memory, 0x0000, listOf(0xB4, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) // LSR Accumulator } @Test fun test_lsr_accumulator_rotates_in_zero_not_carry() { mpu.Status.C = true // $0000 LSR A memory[0x0000] = (0x4A) mpu.A = 0x00 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_accumulator_sets_carry_and_zero_flags_after_rotation() { mpu.Status.C = false // $0000 LSR A memory[0x0000] = (0x4A) mpu.A = 0x01 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_accumulator_rotates_bits_right() { mpu.Status.C = true // $0000 LSR A memory[0x0000] = (0x4A) mpu.A = 0x04 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x02, mpu.A) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) // LSR Absolute } @Test fun test_lsr_absolute_rotates_in_zero_not_carry() { mpu.Status.C = true // $0000 LSR $ABCD writeMem(memory, 0x0000, listOf(0x4E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_absolute_sets_carry_and_zero_flags_after_rotation() { mpu.Status.C = false // $0000 LSR $ABCD writeMem(memory, 0x0000, listOf(0x4E, 0xCD, 0xAB)) memory[0xABCD] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_absolute_rotates_bits_right() { mpu.Status.C = true // $0000 LSR $ABCD writeMem(memory, 0x0000, listOf(0x4E, 0xCD, 0xAB)) memory[0xABCD] = 0x04 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x02, memory[0xABCD]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) // LSR Zero Page } @Test fun test_lsr_zp_rotates_in_zero_not_carry() { mpu.Status.C = true // $0000 LSR $0010 writeMem(memory, 0x0000, listOf(0x46, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_zp_sets_carry_and_zero_flags_after_rotation() { mpu.Status.C = false // $0000 LSR $0010 writeMem(memory, 0x0000, listOf(0x46, 0x10)) memory[0x0010] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_zp_rotates_bits_right() { mpu.Status.C = true // $0000 LSR $0010 writeMem(memory, 0x0000, listOf(0x46, 0x10)) memory[0x0010] = 0x04 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, memory[0x0010]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) // LSR Absolute, X-Indexed } @Test fun test_lsr_abs_x_indexed_rotates_in_zero_not_carry() { mpu.Status.C = true mpu.X = 0x03 // $0000 LSR $ABCD,X writeMem(memory, 0x0000, listOf(0x5E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_abs_x_indexed_sets_c_and_z_flags_after_rotation() { mpu.Status.C = false mpu.X = 0x03 // $0000 LSR $ABCD,X writeMem(memory, 0x0000, listOf(0x5E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x01 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_abs_x_indexed_rotates_bits_right() { mpu.Status.C = true // $0000 LSR $ABCD,X writeMem(memory, 0x0000, listOf(0x5E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x04 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x02, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) // LSR Zero Page, X-Indexed } @Test fun test_lsr_zp_x_indexed_rotates_in_zero_not_carry() { mpu.Status.C = true mpu.X = 0x03 // $0000 LSR $0010,X writeMem(memory, 0x0000, listOf(0x56, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_zp_x_indexed_sets_carry_and_zero_flags_after_rotation() { mpu.Status.C = false mpu.X = 0x03 // $0000 LSR $0010,X writeMem(memory, 0x0000, listOf(0x56, 0x10)) memory[0x0010 + mpu.X] = 0x01 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertTrue(mpu.Status.C) assertFalse(mpu.Status.N) } @Test fun test_lsr_zp_x_indexed_rotates_bits_right() { mpu.Status.C = true mpu.X = 0x03 // $0000 LSR $0010,X writeMem(memory, 0x0000, listOf(0x56, 0x10)) memory[0x0010 + mpu.X] = 0x04 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x02, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) assertFalse(mpu.Status.N) // NOP } @Test fun test_nop_does_nothing() { // $0000 NOP memory[0x0000] = 0xEA mpu.step() assertEquals(0x0001, mpu.PC) // ORA Absolute } @Test fun test_ora_absolute_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 // $0000 ORA $ABCD writeMem(memory, 0x0000, listOf(0x0D, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_absolute_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 // $0000 ORA $ABCD writeMem(memory, 0x0000, listOf(0x0D, 0xCD, 0xAB)) memory[0xABCD] = 0x82 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Zero Page } @Test fun test_ora_zp_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 // $0000 ORA $0010 writeMem(memory, 0x0000, listOf(0x05, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_zp_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 // $0000 ORA $0010 writeMem(memory, 0x0000, listOf(0x05, 0x10)) memory[0x0010] = 0x82 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Immediate } @Test fun test_ora_immediate_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 // $0000 ORA #$00 writeMem(memory, 0x0000, listOf(0x09, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_immediate_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 // $0000 ORA #$82 writeMem(memory, 0x0000, listOf(0x09, 0x82)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Absolute, X } @Test fun test_ora_abs_x_indexed_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.X = 0x03 // $0000 ORA $ABCD,X writeMem(memory, 0x0000, listOf(0x1D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_abs_x_indexed_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 mpu.X = 0x03 // $0000 ORA $ABCD,X writeMem(memory, 0x0000, listOf(0x1D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x82 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Absolute, Y } @Test fun test_ora_abs_y_indexed_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.Y = 0x03 // $0000 ORA $ABCD,Y writeMem(memory, 0x0000, listOf(0x19, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_abs_y_indexed_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 mpu.Y = 0x03 // $0000 ORA $ABCD,Y writeMem(memory, 0x0000, listOf(0x19, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x82 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Indirect, Indexed (X) } @Test fun test_ora_ind_indexed_x_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.X = 0x03 // $0000 ORA ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x01, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_ind_indexed_x_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 mpu.X = 0x03 // $0000 ORA ($0010,X) // $0013 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x01, 0x10)) writeMem(memory, 0x0013, listOf(0xCD, 0xAB)) memory[0xABCD] = 0x82 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Indexed, Indirect (Y) } @Test fun test_ora_indexed_ind_y_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.Y = 0x03 // $0000 ORA ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x11, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_indexed_ind_y_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 mpu.Y = 0x03 // $0000 ORA ($0010),Y // $0010 Vector to $ABCD writeMem(memory, 0x0000, listOf(0x11, 0x10)) writeMem(memory, 0x0010, listOf(0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x82 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // ORA Zero Page, X } @Test fun test_ora_zp_x_indexed_zeroes_or_zeros_sets_z_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.X = 0x03 // $0000 ORA $0010,X writeMem(memory, 0x0000, listOf(0x15, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) } @Test fun test_ora_zp_x_indexed_turns_bits_on_sets_n_flag() { mpu.Status.N = false mpu.A = 0x03 mpu.X = 0x03 // $0000 ORA $0010,X writeMem(memory, 0x0000, listOf(0x15, 0x10)) memory[0x0010 + mpu.X] = 0x82 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x83, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) // PHA } @Test fun test_pha_pushes_a_and_updates_sp() { mpu.A = 0xAB // $0000 PHA memory[0x0000] = 0x48 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xAB, memory[0x01FF]) assertEquals(0xFE, mpu.SP) } // PHP @Test fun test_php_pushes_processor_status_and_updates_sp() { for (flags in 0 until 0x100) { mpu.Status.fromByte(flags or fBREAK or fUNUSED) // $0000 PHP memory[0x0000] = 0x08 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals((flags or fBREAK or fUNUSED), memory[0x1FF].toInt()) assertEquals(0xFE, mpu.SP) } } // PLA @Test fun test_pla_pulls_top_byte_from_stack_into_a_and_updates_sp() { // $0000 PLA memory[0x0000] = 0x68 memory[0x01FF] = 0xAB mpu.SP = 0xFE mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xFF, mpu.SP) // PLP } @Test fun test_plp_pulls_top_byte_from_stack_into_flags_and_updates_sp() { // $0000 PLP memory[0x0000] = 0x28 memory[0x01FF] = 0xBA // must have BREAK and UNUSED set mpu.SP = 0xFE mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xBA, mpu.Status.asByte()) assertEquals(0xFF, mpu.SP) // ROL Accumulator } @Test fun test_rol_accumulator_zero_and_carry_zero_sets_z_flag() { mpu.A = 0x00 mpu.Status.C = false // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_accumulator_80_and_carry_zero_sets_z_flag() { mpu.A = 0x80 mpu.Status.C = false mpu.Status.Z = false // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_accumulator_zero_and_carry_one_clears_z_flag() { mpu.A = 0x00 mpu.Status.C = true // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x01, mpu.A) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_accumulator_sets_n_flag() { mpu.A = 0x40 mpu.Status.C = true // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x81, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_rol_accumulator_shifts_out_zero() { mpu.A = 0x7F mpu.Status.C = false // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFE, mpu.A) assertFalse(mpu.Status.C) } @Test fun test_rol_accumulator_shifts_out_one() { mpu.A = 0xFF mpu.Status.C = false // $0000 ROL A memory[0x0000] = 0x2A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xFE, mpu.A) assertTrue(mpu.Status.C) // ROL Absolute } @Test fun test_rol_absolute_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_absolute_80_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.Status.Z = false // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_absolute_zero_and_carry_one_clears_z_flag() { mpu.A = 0x00 mpu.Status.C = true // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, memory[0xABCD]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_absolute_sets_n_flag() { mpu.Status.C = true // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_rol_absolute_shifts_out_zero() { mpu.Status.C = false // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFE, memory[0xABCD]) assertFalse(mpu.Status.C) } @Test fun test_rol_absolute_shifts_out_one() { mpu.Status.C = false // $0000 ROL $ABCD writeMem(memory, 0x0000, listOf(0x2E, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFE, memory[0xABCD]) assertTrue(mpu.Status.C) // ROL Zero Page } @Test fun test_rol_zp_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_80_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.Status.Z = false // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_zero_and_carry_one_clears_z_flag() { mpu.A = 0x00 mpu.Status.C = true // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, memory[0x0010]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_sets_n_flag() { mpu.Status.C = true // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_rol_zp_shifts_out_zero() { mpu.Status.C = false // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFE, memory[0x0010]) assertFalse(mpu.Status.C) } @Test fun test_rol_zp_shifts_out_one() { mpu.Status.C = false // $0000 ROL $0010 writeMem(memory, 0x0000, listOf(0x26, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFE, memory[0x0010]) assertTrue(mpu.Status.C) // ROL Absolute, X-Indexed } @Test fun test_rol_abs_x_indexed_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.X = 0x03 // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_abs_x_indexed_80_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.Status.Z = false mpu.X = 0x03 // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x80 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_abs_x_indexed_zero_and_carry_one_clears_z_flag() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x01, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_abs_x_indexed_sets_n_flag() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x40 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_rol_abs_x_indexed_shifts_out_zero() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x7F mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFE, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_rol_abs_x_indexed_shifts_out_one() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROL $ABCD,X writeMem(memory, 0x0000, listOf(0x3E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFE, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.C) // ROL Zero Page, X-Indexed } @Test fun test_rol_zp_x_indexed_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x36, 0x10)) // $0000 ROL $0010,X memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_x_indexed_80_and_carry_zero_sets_z_flag() { mpu.Status.C = false mpu.Status.Z = false mpu.X = 0x03 writeMem(memory, 0x0000, listOf(0x36, 0x10)) // $0000 ROL $0010,X memory[0x0010 + mpu.X] = 0x80 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_x_indexed_zero_and_carry_one_clears_z_flag() { mpu.X = 0x03 mpu.Status.C = true writeMem(memory, 0x0000, listOf(0x36, 0x10)) // $0000 ROL $0010,X memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x01, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_rol_zp_x_indexed_sets_n_flag() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROL $0010,X writeMem(memory, 0x0000, listOf(0x36, 0x10)) memory[0x0010 + mpu.X] = 0x40 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.N) assertFalse(mpu.Status.Z) } @Test fun test_rol_zp_x_indexed_shifts_out_zero() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROL $0010,X writeMem(memory, 0x0000, listOf(0x36, 0x10)) memory[0x0010 + mpu.X] = 0x7F mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFE, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_rol_zp_x_indexed_shifts_out_one() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROL $0010,X writeMem(memory, 0x0000, listOf(0x36, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFE, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.C) // ROR Accumulator } @Test fun test_ror_accumulator_zero_and_carry_zero_sets_z_flag() { mpu.A = 0x00 mpu.Status.C = false // $0000 ROR A memory[0x0000] = 0x6A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_ror_accumulator_zero_and_carry_one_rotates_in_sets_n_flags() { mpu.A = 0x00 mpu.Status.C = true // $0000 ROR A memory[0x0000] = 0x6A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_ror_accumulator_shifts_out_zero() { mpu.A = 0x02 mpu.Status.C = true // $0000 ROR A memory[0x0000] = 0x6A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x81, mpu.A) assertFalse(mpu.Status.C) } @Test fun test_ror_accumulator_shifts_out_one() { mpu.A = 0x03 mpu.Status.C = true // $0000 ROR A memory[0x0000] = 0x6A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x81, mpu.A) assertTrue(mpu.Status.C) // ROR Absolute } @Test fun test_ror_absolute_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false // $0000 ROR $ABCD writeMem(memory, 0x0000, listOf(0x6E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_ror_absolute_zero_and_carry_one_rotates_in_sets_n_flags() { mpu.Status.C = true // $0000 ROR $ABCD writeMem(memory, 0x0000, listOf(0x6E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_ror_absolute_shifts_out_zero() { mpu.Status.C = true // $0000 ROR $ABCD writeMem(memory, 0x0000, listOf(0x6E, 0xCD, 0xAB)) memory[0xABCD] = 0x02 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD]) assertFalse(mpu.Status.C) } @Test fun test_ror_absolute_shifts_out_one() { mpu.Status.C = true // $0000 ROR $ABCD writeMem(memory, 0x0000, listOf(0x6E, 0xCD, 0xAB)) memory[0xABCD] = 0x03 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD]) assertTrue(mpu.Status.C) // ROR Zero Page } @Test fun test_ror_zp_zero_and_carry_zero_sets_z_flag() { mpu.Status.C = false // $0000 ROR $0010 writeMem(memory, 0x0000, listOf(0x66, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_ror_zp_zero_and_carry_one_rotates_in_sets_n_flags() { mpu.Status.C = true // $0000 ROR $0010 writeMem(memory, 0x0000, listOf(0x66, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_ror_zp_zero_absolute_shifts_out_zero() { mpu.Status.C = true // $0000 ROR $0010 writeMem(memory, 0x0000, listOf(0x66, 0x10)) memory[0x0010] = 0x02 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010]) assertFalse(mpu.Status.C) } @Test fun test_ror_zp_shifts_out_one() { mpu.Status.C = true // $0000 ROR $0010 writeMem(memory, 0x0000, listOf(0x66, 0x10)) memory[0x0010] = 0x03 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010]) assertTrue(mpu.Status.C) // ROR Absolute, X-Indexed } @Test fun test_ror_abs_x_indexed_zero_and_carry_zero_sets_z_flag() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROR $ABCD,X writeMem(memory, 0x0000, listOf(0x7E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_ror_abs_x_indexed_z_and_c_1_rotates_in_sets_n_flags() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $ABCD,X writeMem(memory, 0x0000, listOf(0x7E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x80, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_ror_abs_x_indexed_shifts_out_zero() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $ABCD,X writeMem(memory, 0x0000, listOf(0x7E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x02 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_ror_abs_x_indexed_shifts_out_one() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $ABCD,X writeMem(memory, 0x0000, listOf(0x7E, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x03 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x81, memory[0xABCD + mpu.X]) assertTrue(mpu.Status.C) // ROR Zero Page, X-Indexed } @Test fun test_ror_zp_x_indexed_zero_and_carry_zero_sets_z_flag() { mpu.X = 0x03 mpu.Status.C = false // $0000 ROR $0010,X writeMem(memory, 0x0000, listOf(0x76, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.Z) assertFalse(mpu.Status.N) } @Test fun test_ror_zp_x_indexed_zero_and_carry_one_rotates_in_sets_n_flags() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $0010,X writeMem(memory, 0x0000, listOf(0x76, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x80, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.N) } @Test fun test_ror_zp_x_indexed_zero_absolute_shifts_out_zero() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $0010,X writeMem(memory, 0x0000, listOf(0x76, 0x10)) memory[0x0010 + mpu.X] = 0x02 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010 + mpu.X]) assertFalse(mpu.Status.C) } @Test fun test_ror_zp_x_indexed_shifts_out_one() { mpu.X = 0x03 mpu.Status.C = true // $0000 ROR $0010,X writeMem(memory, 0x0000, listOf(0x76, 0x10)) memory[0x0010 + mpu.X] = 0x03 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x81, memory[0x0010 + mpu.X]) assertTrue(mpu.Status.C) // RTI } @Test fun test_rti_restores_status_and_pc_and_updates_sp() { // $0000 RTI memory[0x0000] = 0x40 writeMem(memory, 0x01FD, listOf(0xFC, 0x03, 0xC0)) // Status, PCL, PCH mpu.SP = 0xFC mpu.step() assertEquals(0xC003, mpu.PC) assertEquals(0xFC, mpu.Status.asByte()) assertEquals(0xFF, mpu.SP) } @Test fun test_rti_forces_break_and_unused_flags_high() { // $0000 RTI memory[0x0000] = 0x40 writeMem(memory, 0x01FD, listOf(0x00, 0x03, 0xC0)) // Status, PCL, PCH mpu.SP = 0xFC mpu.step() assertTrue(mpu.Status.B) // assertEquals(fUNUSED, mpu.Status.asByte().toInt() and fUNUSED) } // RTS @Test fun test_rts_restores_pc_and_increments_then_updates_sp() { // $0000 RTS memory[0x0000] = 0x60 writeMem(memory, 0x01FE, listOf(0x03, 0xC0)) // PCL, PCH mpu.PC = 0x0000 mpu.SP = 0xFD mpu.step() assertEquals(0xC004, mpu.PC) assertEquals(0xFF, mpu.SP) } @Test fun test_rts_wraps_around_top_of_memory() { // $1000 RTS memory[0x1000] = 0x60 writeMem(memory, 0x01FE, listOf(0xFF, 0xFF)) // PCL, PCH mpu.PC = 0x1000 mpu.SP = 0xFD mpu.step() assertEquals(0x0000, mpu.PC) assertEquals(0xFF, mpu.SP) } // SBC Absolute @Test fun test_sbc_abs_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC $ABCD writeMem(memory, 0x0000, listOf(0xED, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC $ABCD writeMem(memory, 0x0000, listOf(0xED, 0xCD, 0xAB)) memory[0xABCD] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC $ABCD writeMem(memory, 0x0000, listOf(0xED, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC $ABCD writeMem(memory, 0x0000, listOf(0xED, 0xCD, 0xAB)) memory[0xABCD] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Zero Page @Test fun test_sbc_zp_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC $10 writeMem(memory, 0x0000, listOf(0xE5, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC $10 writeMem(memory, 0x0000, listOf(0xE5, 0x10)) memory[0x0010] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // => SBC $10 writeMem(memory, 0x0000, listOf(0xE5, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // => SBC $10 writeMem(memory, 0x0000, listOf(0xE5, 0x10)) memory[0x0010] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Immediate @Test fun test_sbc_imm_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xE9, 0x00)) mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_imm_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC #$01 writeMem(memory, 0x0000, listOf(0xE9, 0x01)) mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_imm_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xE9, 0x00)) mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_imm_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC #$02 writeMem(memory, 0x0000, listOf(0xE9, 0x02)) mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } @Test fun test_sbc_bcd_on_immediate_0a_minus_00_carry_set() { mpu.Status.D = true mpu.Status.C = true mpu.A = 0x0a // $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xe9, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x0a, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.V) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } @Test fun test_sbc_bcd_on_immediate_9a_minus_00_carry_set() { mpu.Status.D = true mpu.Status.C = true mpu.A = 0x9a // $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xe9, 0x00)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x9a, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.V) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } @Test fun test_sbc_bcd_on_immediate_00_minus_01_carry_set() { mpu.Status.D = true mpu.Status.V = true mpu.Status.Z = true mpu.Status.C = true mpu.Status.N = false mpu.A = 0x00 // => $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xe9, 0x01)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x99, mpu.A) assertTrue(mpu.Status.N) assertFalse(mpu.Status.V) assertFalse(mpu.Status.Z) assertFalse(mpu.Status.C) } @Test fun test_sbc_bcd_on_immediate_20_minus_0a_carry_unset() { mpu.Status.D = true mpu.A = 0x20 // $0000 SBC #$00 writeMem(memory, 0x0000, listOf(0xe9, 0x0a)) mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x1f, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.V) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Absolute, X-Indexed @Test fun test_sbc_abs_x_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC $FEE0,X writeMem(memory, 0x0000, listOf(0xFD, 0xE0, 0xFE)) mpu.X = 0x0D memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_x_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC $FEE0,X writeMem(memory, 0x0000, listOf(0xFD, 0xE0, 0xFE)) mpu.X = 0x0D memory[0xFEED] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_x_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC $FEE0,X writeMem(memory, 0x0000, listOf(0xFD, 0xE0, 0xFE)) mpu.X = 0x0D memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_x_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC $FEE0,X writeMem(memory, 0x0000, listOf(0xFD, 0xE0, 0xFE)) mpu.X = 0x0D memory[0xFEED] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Absolute, Y-Indexed @Test fun test_sbc_abs_y_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC $FEE0,Y writeMem(memory, 0x0000, listOf(0xF9, 0xE0, 0xFE)) mpu.Y = 0x0D memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_y_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC $FEE0,Y writeMem(memory, 0x0000, listOf(0xF9, 0xE0, 0xFE)) mpu.Y = 0x0D memory[0xFEED] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_y_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC $FEE0,Y writeMem(memory, 0x0000, listOf(0xF9, 0xE0, 0xFE)) mpu.Y = 0x0D memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_abs_y_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC $FEE0,Y writeMem(memory, 0x0000, listOf(0xF9, 0xE0, 0xFE)) mpu.Y = 0x0D memory[0xFEED] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Indirect, Indexed (X) @Test fun test_sbc_ind_x_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC ($10,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0xE1, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) mpu.X = 0x03 memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_x_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC ($10,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0xE1, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) mpu.X = 0x03 memory[0xFEED] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_x_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC ($10,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0xE1, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) mpu.X = 0x03 memory[0xFEED] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_x_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC ($10,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0xE1, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) mpu.X = 0x03 memory[0xFEED] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) } // SBC Indexed, Indirect (Y) @Test fun test_sbc_ind_y_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 mpu.Y = 0x03 // $0000 SBC ($10),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0xF1, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_y_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC ($10),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0xF1, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_y_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC ($10),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0xF1, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_ind_y_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC ($10),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0xF1, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // SBC Zero Page, X-Indexed } @Test fun test_sbc_zp_x_all_zeros_and_no_borrow_is_zero() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x00 // $0000 SBC $10,X writeMem(memory, 0x0000, listOf(0xF5, 0x10)) mpu.X = 0x0D memory[0x001D] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_x_downto_zero_no_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = true // borrow = 0 mpu.A = 0x01 // $0000 SBC $10,X writeMem(memory, 0x0000, listOf(0xF5, 0x10)) mpu.X = 0x0D memory[0x001D] = 0x01 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_x_downto_zero_with_borrow_sets_z_clears_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x01 // $0000 SBC $10,X writeMem(memory, 0x0000, listOf(0xF5, 0x10)) mpu.X = 0x0D memory[0x001D] = 0x00 mpu.step() assertEquals(0x00, mpu.A) assertFalse(mpu.Status.N) assertTrue(mpu.Status.C) assertTrue(mpu.Status.Z) } @Test fun test_sbc_zp_x_downto_four_with_borrow_clears_z_n() { mpu.Status.D = false mpu.Status.C = false // borrow = 1 mpu.A = 0x07 // $0000 SBC $10,X writeMem(memory, 0x0000, listOf(0xF5, 0x10)) mpu.X = 0x0D memory[0x001D] = 0x02 mpu.step() assertEquals(0x04, mpu.A) assertFalse(mpu.Status.N) assertFalse(mpu.Status.Z) assertTrue(mpu.Status.C) // SEC } @Test fun test_sec_sets_carry_flag() { mpu.Status.C = false // $0000 SEC memory[0x0000] = 0x038 mpu.step() assertEquals(0x0001, mpu.PC) assertTrue(mpu.Status.C) // SED } @Test fun test_sed_sets_decimal_mode_flag() { mpu.Status.D = false // $0000 SED memory[0x0000] = 0xF8 mpu.step() assertEquals(0x0001, mpu.PC) assertTrue(mpu.Status.D) } // SEI @Test fun test_sei_sets_interrupt_disable_flag() { mpu.Status.I = false // $0000 SEI memory[0x0000] = 0x78 mpu.step() assertEquals(0x0001, mpu.PC) assertTrue(mpu.Status.I) } // STA Absolute @Test fun test_sta_absolute_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF // $0000 STA $ABCD writeMem(memory, 0x0000, listOf(0x8D, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_absolute_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 // $0000 STA $ABCD writeMem(memory, 0x0000, listOf(0x8D, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) // STA Zero Page } @Test fun test_sta_zp_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF // $0000 STA $0010 writeMem(memory, 0x0000, listOf(0x85, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_zp_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 // $0000 STA $0010 writeMem(memory, 0x0000, listOf(0x85, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) // STA Absolute, X-Indexed } @Test fun test_sta_abs_x_indexed_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF mpu.X = 0x03 // $0000 STA $ABCD,X writeMem(memory, 0x0000, listOf(0x9D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD + mpu.X]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_abs_x_indexed_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 mpu.X = 0x03 // $0000 STA $ABCD,X writeMem(memory, 0x0000, listOf(0x9D, 0xCD, 0xAB)) memory[0xABCD + mpu.X] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.X]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } // STA Absolute, Y-Indexed @Test fun test_sta_abs_y_indexed_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF mpu.Y = 0x03 // $0000 STA $ABCD,Y writeMem(memory, 0x0000, listOf(0x99, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD + mpu.Y]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_abs_y_indexed_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 mpu.Y = 0x03 // $0000 STA $ABCD,Y writeMem(memory, 0x0000, listOf(0x99, 0xCD, 0xAB)) memory[0xABCD + mpu.Y] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD + mpu.Y]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } // STA Indirect, Indexed (X) @Test fun test_sta_ind_indexed_x_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF mpu.X = 0x03 // $0000 STA ($0010,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0x81, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) memory[0xFEED] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0xFEED]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_ind_indexed_x_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 mpu.X = 0x03 // $0000 STA ($0010,X) // $0013 Vector to $FEED writeMem(memory, 0x0000, listOf(0x81, 0x10)) writeMem(memory, 0x0013, listOf(0xED, 0xFE)) memory[0xFEED] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0xFEED]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } // STA Indexed, Indirect (Y) @Test fun test_sta_indexed_ind_y_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF mpu.Y = 0x03 // $0000 STA ($0010),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0x91, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0xFEED + mpu.Y]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_indexed_ind_y_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 mpu.Y = 0x03 // $0000 STA ($0010),Y // $0010 Vector to $FEED writeMem(memory, 0x0000, listOf(0x91, 0x10)) writeMem(memory, 0x0010, listOf(0xED, 0xFE)) memory[0xFEED + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0xFEED + mpu.Y]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } // STA Zero Page, X-Indexed @Test fun test_sta_zp_x_indexed_stores_a_leaves_a_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.A = 0xFF mpu.X = 0x03 // $0000 STA $0010,X writeMem(memory, 0x0000, listOf(0x95, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010 + mpu.X]) assertEquals(0xFF, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sta_zp_x_indexed_stores_a_leaves_a_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.A = 0x00 mpu.X = 0x03 // $0000 STA $0010,X writeMem(memory, 0x0000, listOf(0x95, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertEquals(0x00, mpu.A) assertEquals(flags, mpu.Status.asByte().toInt()) } // STX Absolute @Test fun test_stx_absolute_stores_x_leaves_x_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.X = 0xFF // $0000 STX $ABCD writeMem(memory, 0x0000, listOf(0x8E, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD]) assertEquals(0xFF, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_stx_absolute_stores_x_leaves_x_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.X = 0x00 // $0000 STX $ABCD writeMem(memory, 0x0000, listOf(0x8E, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertEquals(0x00, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } // STX Zero Page @Test fun test_stx_zp_stores_x_leaves_x_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.X = 0xFF // $0000 STX $0010 writeMem(memory, 0x0000, listOf(0x86, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010]) assertEquals(0xFF, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_stx_zp_stores_x_leaves_x_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.X = 0x00 // $0000 STX $0010 writeMem(memory, 0x0000, listOf(0x86, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertEquals(0x00, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } // STX Zero Page, Y-Indexed @Test fun test_stx_zp_y_indexed_stores_x_leaves_x_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.X = 0xFF mpu.Y = 0x03 // $0000 STX $0010,Y writeMem(memory, 0x0000, listOf(0x96, 0x10)) memory[0x0010 + mpu.Y] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010 + mpu.Y]) assertEquals(0xFF, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_stx_zp_y_indexed_stores_x_leaves_x_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.X = 0x00 mpu.Y = 0x03 // $0000 STX $0010,Y writeMem(memory, 0x0000, listOf(0x96, 0x10)) memory[0x0010 + mpu.Y] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.Y]) assertEquals(0x00, mpu.X) assertEquals(flags, mpu.Status.asByte().toInt()) } // STY Absolute @Test fun test_sty_absolute_stores_y_leaves_y_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.Y = 0xFF // $0000 STY $ABCD writeMem(memory, 0x0000, listOf(0x8C, 0xCD, 0xAB)) memory[0xABCD] = 0x00 mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0xFF, memory[0xABCD]) assertEquals(0xFF, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sty_absolute_stores_y_leaves_y_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.Y = 0x00 // $0000 STY $ABCD writeMem(memory, 0x0000, listOf(0x8C, 0xCD, 0xAB)) memory[0xABCD] = 0xFF mpu.step() assertEquals(0x0003, mpu.PC) assertEquals(0x00, memory[0xABCD]) assertEquals(0x00, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } // STY Zero Page @Test fun test_sty_zp_stores_y_leaves_y_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.Y = 0xFF // $0000 STY $0010 writeMem(memory, 0x0000, listOf(0x84, 0x10)) memory[0x0010] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010]) assertEquals(0xFF, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sty_zp_stores_y_leaves_y_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.Y = 0x00 // $0000 STY $0010 writeMem(memory, 0x0000, listOf(0x84, 0x10)) memory[0x0010] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010]) assertEquals(0x00, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } // STY Zero Page, X-Indexed @Test fun test_sty_zp_x_indexed_stores_y_leaves_y_and_n_flag_unchanged() { val flags = 0xFF and fNEGATIVE.inv() mpu.Status.fromByte(flags) mpu.Y = 0xFF mpu.X = 0x03 // $0000 STY $0010,X writeMem(memory, 0x0000, listOf(0x94, 0x10)) memory[0x0010 + mpu.X] = 0x00 mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0xFF, memory[0x0010 + mpu.X]) assertEquals(0xFF, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } @Test fun test_sty_zp_x_indexed_stores_y_leaves_y_and_z_flag_unchanged() { val flags = 0xFF and fZERO.inv() mpu.Status.fromByte(flags) mpu.Y = 0x00 mpu.X = 0x03 // $0000 STY $0010,X writeMem(memory, 0x0000, listOf(0x94, 0x10)) memory[0x0010 + mpu.X] = 0xFF mpu.step() assertEquals(0x0002, mpu.PC) assertEquals(0x00, memory[0x0010 + mpu.X]) assertEquals(0x00, mpu.Y) assertEquals(flags, mpu.Status.asByte().toInt()) } // TAX @Test fun test_tax_transfers_accumulator_into_x() { mpu.A = 0xAB mpu.X = 0x00 // $0000 TAX memory[0x0000] = 0xAA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xAB, mpu.X) } @Test fun test_tax_sets_negative_flag() { mpu.Status.N = false mpu.A = 0x80 mpu.X = 0x00 // $0000 TAX memory[0x0000] = 0xAA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) } @Test fun test_tax_sets_zero_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.X = 0xFF // $0000 TAX memory[0x0000] = 0xAA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) } // TAY @Test fun test_tay_transfers_accumulator_into_y() { mpu.A = 0xAB mpu.Y = 0x00 // $0000 TAY memory[0x0000] = 0xA8 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xAB, mpu.Y) } @Test fun test_tay_sets_negative_flag() { mpu.Status.N = false mpu.A = 0x80 mpu.Y = 0x00 // $0000 TAY memory[0x0000] = 0xA8 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) } @Test fun test_tay_sets_zero_flag() { mpu.Status.Z = false mpu.A = 0x00 mpu.Y = 0xFF // $0000 TAY memory[0x0000] = 0xA8 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) } // TSX @Test fun test_tsx_transfers_stack_pointer_into_x() { mpu.SP = 0xAB mpu.X = 0x00 // $0000 TSX memory[0x0000] = 0xBA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.SP) assertEquals(0xAB, mpu.X) } @Test fun test_tsx_sets_negative_flag() { mpu.Status.N = false mpu.SP = 0x80 mpu.X = 0x00 // $0000 TSX memory[0x0000] = 0xBA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.SP) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) } @Test fun test_tsx_sets_zero_flag() { mpu.Status.Z = false mpu.SP = 0x00 mpu.Y = 0xFF // $0000 TSX memory[0x0000] = 0xBA mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.SP) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) } // TXA @Test fun test_txa_transfers_x_into_a() { mpu.X = 0xAB mpu.A = 0x00 // $0000 TXA memory[0x0000] = 0x8A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xAB, mpu.X) } @Test fun test_txa_sets_negative_flag() { mpu.Status.N = false mpu.X = 0x80 mpu.A = 0x00 // $0000 TXA memory[0x0000] = 0x8A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertEquals(0x80, mpu.X) assertTrue(mpu.Status.N) } @Test fun test_txa_sets_zero_flag() { mpu.Status.Z = false mpu.X = 0x00 mpu.A = 0xFF // $0000 TXA memory[0x0000] = 0x8A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.A) assertEquals(0x00, mpu.X) assertTrue(mpu.Status.Z) } // TXS @Test fun test_txs_transfers_x_into_stack_pointer() { mpu.X = 0xAB // $0000 TXS memory[0x0000] = 0x9A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.SP) assertEquals(0xAB, mpu.X) } @Test fun test_txs_does_not_set_negative_flag() { mpu.Status.N = false mpu.X = 0x80 // $0000 TXS memory[0x0000] = 0x9A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.SP) assertEquals(0x80, mpu.X) assertFalse(mpu.Status.N) } @Test fun test_txs_does_not_set_zero_flag() { mpu.Status.Z = false mpu.X = 0x00 // $0000 TXS memory[0x0000] = 0x9A mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x00, mpu.SP) assertEquals(0x00, mpu.X) assertFalse(mpu.Status.Z) } // TYA @Test fun test_tya_transfers_y_into_a() { mpu.Y = 0xAB mpu.A = 0x00 // $0000 TYA memory[0x0000] = 0x98 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0xAB, mpu.A) assertEquals(0xAB, mpu.Y) } @Test fun test_tya_sets_negative_flag() { mpu.Status.N = false mpu.Y = 0x80 mpu.A = 0x00 // $0000 TYA memory[0x0000] = 0x98 mpu.step() assertEquals(0x0001, mpu.PC) assertEquals(0x80, mpu.A) assertEquals(0x80, mpu.Y) assertTrue(mpu.Status.N) } @Test fun test_tya_sets_zero_flag() { mpu.Status.Z = false mpu.Y = 0x00 mpu.A = 0xFF // $0000 TYA memory[0x0000] = 0x98 mpu.step() assertEquals(0x00, mpu.A) assertEquals(0x00, mpu.Y) assertTrue(mpu.Status.Z) assertEquals(0x0001, mpu.PC) } @Test fun test_brk_interrupt() { writeMem(memory, 0xFFFE, listOf(0x00, 0x04)) writeMem(memory, 0x0000, listOf(0xA9, 0x01, // LDA #$01 0x00, 0xEA, // BRK + skipped byte 0xEA, 0xEA, // NOP, NOP 0xA9, 0x03)) // LDA #$03 writeMem(memory, 0x0400, listOf(0xA9, 0x02, // LDA #$02 0x40)) // RTI mpu.step() // LDA #$01 assertEquals(0x01, mpu.A) assertEquals(0x0002, mpu.PC) mpu.step() // BRK assertEquals(0x0400, mpu.PC) mpu.step() // LDA #$02 assertEquals(0x02, mpu.A) assertEquals(0x0402, mpu.PC) mpu.step() // RTI assertEquals(0x0004, mpu.PC) mpu.step() // A NOP mpu.step() // The second NOP mpu.step() // LDA #$03 assertEquals(0x03, mpu.A) assertEquals(0x0008, mpu.PC) } }