Added 65C02 instruction LDA (ZP)

src/py65/assembler.py

@@ -8,6 +8,7 @@ class Assembler:
                            r'[,xXyY\s]*)$')
                            
     Addressing = [
+        ['zpi', re.compile(r'^\(\$00([0-9A-F]{2})\)$')],            # "($0012)"
         ['zpx', re.compile(r'^\$00([0-9A-F]{2}),X$')],              # "$0012,X"
         ['zpy', re.compile(r'^\$00([0-9A-F]{2}),Y$')],              # "$0012,Y"
         ['zpg', re.compile(r'^\$00([0-9A-F]{2})$')],                # "$0012"

src/py65/devices/mpu65c02.py

@@ -14,6 +14,11 @@ class MPU(NMOS6502):
     instruction = make_instruction_decorator(instruct, disassemble, 
                                                 cycletime, extracycles)
 
+    # addressing modes
+
+    def ZeroPageIndirectAddr(self):
+        return self.WordAt( 255 & (self.ByteAt(self.pc)))
+
     # operations
 
     def opSTZ(self, x):
@@ -66,7 +71,12 @@ class MPU(NMOS6502):
     @instruction(name="STZ", mode="abx", cycles=5)
     def i9e(self):
         self.opSTZ(self.AbsoluteXAddr)
-        self.pc+=2
+        self.pc += 2
+
+    @instruction(name="LDA", mode="zpi", cycles=5)
+    def ib2(self):
+        self.opLDA(self.ZeroPageIndirectAddr)
+        self.pc += 1
 
     @instruction(name="PHX", mode="imp", cycles=3)
     def ida(self):

src/py65/disassembler.py

@@ -79,6 +79,13 @@ class Disassembler:
             disasm += ' ' + address_or_label
             length = 2
 
+        elif addressing == 'zpi':
+            zp_address = self._mpu.ByteAt(pc + 1)
+            address_or_label = self._address_parser.label_for(zp_address, 
+                '($%02x)' % zp_address)
+            disasm += ' %s' % address_or_label
+            length = 2
+
         elif addressing == 'zpg':
             zp_address = self._mpu.ByteAt(pc + 1)
             address_or_label = self._address_parser.label_for(zp_address, 

src/py65/monitor.py

@@ -6,7 +6,7 @@ import re
 import shlex
 import asyncore
 import sys
-from py65.devices.mpu6502 import MPU
+from py65.devices.mpu65c02 import MPU
 from py65.disassembler import Disassembler
 from py65.assembler import Assembler
 from py65.utils.addressing import AddressParser

src/py65/tests/devices/test_mpu65c02.py

@@ -12,6 +12,32 @@ class MPUTests(unittest.TestCase, Common6502Tests):
         self.assertEquals('<65C02: A=00, X=00, Y=00, Flags=20, SP=ff, PC=0000>',
                           repr(mpu))
 
+    # LDA Zero Page, Indirect
+
+    def test_lda_zp_indirect_loads_a_sets_n_flag(self):
+        mpu = self._make_mpu()
+        mpu.a = 0x00
+        self._write(mpu.memory, 0x0000, (0xB2, 0x10)) #=> LDA ($0010)
+        self._write(mpu.memory, 0x0010, (0xCD, 0xAB)) #=> Vector to $ABCD
+        mpu.memory[0xABCD] = 0x80
+        mpu.step()
+        self.assertEquals(0x0002, mpu.pc)
+        self.assertEquals(0x80, mpu.a)
+        self.assertEquals(mpu.NEGATIVE, mpu.flags & mpu.NEGATIVE)
+        self.assertEquals(0, mpu.flags & mpu.ZERO)
+
+    def test_lda_zp_indirect_loads_a_sets_z_flag(self):
+        mpu = self._make_mpu()
+        mpu.a = 0x00
+        self._write(mpu.memory, 0x0000, (0xB2, 0x10)) #=> LDA ($0010)
+        self._write(mpu.memory, 0x0010, (0xCD, 0xAB)) #=> Vector to $ABCD
+        mpu.memory[0xABCD] = 0x00
+        mpu.step()
+        self.assertEquals(0x0002, mpu.pc)
+        self.assertEquals(0x00, mpu.a)
+        self.assertEquals(mpu.ZERO, mpu.flags & mpu.ZERO)
+        self.assertEquals(0, mpu.flags & mpu.NEGATIVE)
+
     # PHX
   
     def test_phx_pushes_x_and_updates_sp(self):