mirror of
https://github.com/TomHarte/CLK.git
synced 2024-12-27 16:31:31 +00:00
74 lines
2.5 KiB
Swift
74 lines
2.5 KiB
Swift
//
|
|
// 6502InterruptTests.swift
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 28/06/2016.
|
|
// Copyright © 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
import XCTest
|
|
|
|
class MOS6502InterruptTests: XCTestCase {
|
|
|
|
var machine: CSTestMachine! = nil
|
|
override func setUp() {
|
|
super.setUp()
|
|
|
|
// create a machine full of NOPs
|
|
machine = CSTestMachine()
|
|
for c in 0...65535 {
|
|
machine.setValue(0xea, forAddress: UInt16(c))
|
|
}
|
|
|
|
// set the IRQ vector to be 0x1234
|
|
machine.setValue(0x34, forAddress: 0xfffe)
|
|
machine.setValue(0x12, forAddress: 0xffff)
|
|
|
|
// add a CLI
|
|
machine.setValue(0x58, forAddress: 0x4000)
|
|
|
|
// pick things off at 0x4000
|
|
machine.setValue(0x4000, forRegister: CSTestMachineRegister.ProgramCounter)
|
|
}
|
|
|
|
func testIRQLine() {
|
|
// run for six cycles; check that no interrupt has occurred
|
|
machine.runForNumberOfCycles(6)
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x4003, "No interrupt should have occurred with line low")
|
|
|
|
// enable the interrupt line, check that it was too late
|
|
machine.irqLine = true
|
|
machine.runForNumberOfCycles(2)
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x4004, "No interrupt should have occurred from interrupt raised between instructions")
|
|
|
|
// run for a further 7 cycles, confirm that the IRQ vector was jumped to
|
|
machine.runForNumberOfCycles(7)
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x1234, "Interrupt routine should just have begun")
|
|
}
|
|
|
|
func testIFlagSet() {
|
|
// enable the interrupt line, run for eleven cycles to get past the CLIP and the following NOP and into the interrupt routine
|
|
machine.irqLine = true
|
|
machine.runForNumberOfCycles(11)
|
|
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x1234, "Interrupt routine should just have begun")
|
|
XCTAssert(machine.valueForRegister(.Flags) & 0x04 == 0x04, "Interrupt status flag should be set")
|
|
}
|
|
|
|
func testCLISEIFlagClear() {
|
|
// set up an SEI as the second instruction, enable the IRQ line
|
|
machine.setValue(0x78, forAddress: 0x4001)
|
|
machine.irqLine = true
|
|
|
|
// run for four cycles; the CLI and SEI should have been performed
|
|
machine.runForNumberOfCycles(4)
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x4002, "CLI/SEI pair should have been performed in their entirety")
|
|
|
|
// run for seven more cycles
|
|
machine.runForNumberOfCycles(7)
|
|
|
|
// interrupt should have taken place despite SEI
|
|
XCTAssert(machine.valueForRegister(.ProgramCounter) == 0x1234, "Interrupt routine should just have begun")
|
|
}
|
|
}
|