def test_TYA():
cpu = CPU()
memory = Memory()
cpu.a = 1
cpu.y = 2
TYA = OpCodes.all[152]
TYA.exec(cpu, memory)
assert cpu.a == 2
assert cpu.zero == False
assert cpu.negative == False
cpu.y = 0
cpu.a = 1
cpu.inc_cycle_by(-cpu.cycle)
TYA.exec(cpu, memory)
assert cpu.cycle == (TYA.cycles - 1)
assert cpu.a == 0
assert cpu.zero == True
assert cpu.negative == False
cpu.y = 0b10000001
cpu.a = 1
TYA.exec(cpu, memory)
assert cpu.a == 0b10000001
assert cpu.zero == False
print(cpu.negative)
assert cpu.negative == True
def test_TAY():
cpu = CPU()
memory = Memory()
cpu.y = 1
cpu.a = 2
TAY = OpCodes.all[168]
TAY.exec(cpu, memory)
assert cpu.y == 2
assert cpu.zero == False
assert cpu.negative == False
cpu.a = 0
cpu.y = 1
cpu.inc_cycle_by(-cpu.cycle)
TAY.exec(cpu, memory)
assert cpu.cycle == (TAY.cycles - 1)
assert cpu.y == 0
assert cpu.zero == True
assert cpu.negative == False
cpu.a = 0b10000001
cpu.y = 1
TAY.exec(cpu, memory)
assert cpu.y == 0b10000001
assert cpu.zero == False
print(cpu.negative)
assert cpu.negative == True
def test_read_AbsoluteY():
address_mode = AbsoluteY
cpu = CPU()
memory = Memory(rom=[0x32, 0x02, 0x7F, 0x01, 0x00, 0x20],
ram=list(map(lambda x: x % 256, range(Memory.ram_size()))))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 0x0A
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 0x023C
assert value == (0x023C % 256)
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0xA1
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 0x0220
assert value == (0x0220 % 256)
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0x07
address = address_mode.fetch_address(cpu, memory)
assert address == 0x2007
def test_write_AbsoluteY():
address_mode = AbsoluteY
cpu = CPU()
memory = Memory(rom=[0x30, 0x01, 0xFF, 0x02, 0x0A, 0x05],
ram=list(map(lambda x: x % 256, range(Memory.ram_size()))))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 0x25
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 20)
assert address == 0x0155
assert memory.ram[address] == 20
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0x30
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 100)
assert address == 0x032F
assert memory.ram[address] == 100
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0x20
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 67)
assert address == 0x052A
assert memory.ram[address] == 67
def test_write_ZeroPageY():
address_mode = ZeroPageY
cpu = CPU()
memory = Memory(rom=list(range(256)))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 5
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 6)
assert address == 5
assert memory.ram[address] == 6
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 20)
cpu.y = 15
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 105)
assert address == 35
assert memory.ram[address] == 105
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 100)
cpu.y = 155
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 143)
assert address == 255
assert memory.ram[address] == 143
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 255)
cpu.y = 0
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 255)
assert address == 255
assert memory.ram[address] == 255
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 255)
cpu.y = 75
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 255)
assert address == 74
assert memory.ram[address] == 255
assert cpu.cycle == 3
def test_read_ZeroPageY():
address_mode = ZeroPageY
cpu = CPU()
memory = Memory(rom=list(range(256)), ram=list(reversed(range(256))))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 1
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 1
assert value == 254
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 20)
cpu.y = 10
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 30
assert value == 225
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 100)
cpu.y = 5
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 105
assert value == 150
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 255)
cpu.y = 0
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 255
assert value == 0
assert cpu.cycle == 3
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start + 255)
cpu.y = 5
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 4
assert value == 251
assert cpu.cycle == 3
def test_read_IndirectY():
address_mode = IndirectY
cpu = CPU()
memory = Memory(rom=[0x00, 0x02, 0x7F, 0x01, 0xFF, 0x07],
ram=list(map(lambda x: x % 256, range(Memory.ram_size()))))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 4
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 0x0104
assert value == address % 256
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0xFF
address = address_mode.fetch_address(cpu, memory)
value = address_mode.read_from(cpu, memory, address)
assert address == 0x0401
assert value == address % 256
def test_write_IndirectY():
address_mode = IndirectY
cpu = CPU()
memory = Memory(rom=[0x00, 0x02, 0x7F, 0x01, 0xFF, 0x07],
ram=list(map(lambda x: x % 256, range(Memory.ram_size()))))
cpu.inc_cycle_by(-cpu.cycle)
cpu.inc_pc_by(-cpu.pc + MemoryPositions.PRG_ROM_START.start)
cpu.y = 4
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 9)
assert address == 0x0104
assert memory.ram[address] == 9
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0xFF
address = address_mode.fetch_address(cpu, memory)
address_mode.write_to(cpu, memory, address, 50)
assert address == 0x0401
assert memory.ram[address] == 50
def test_DEY_negative():
instruction = OpCodes.all[0x88]
cpu = CPU()
memory = Memory()
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 0
instruction.exec(cpu, memory)
assert cpu.cycle == (instruction.cycles - 1)
assert cpu.y == 255
assert cpu.zero == False
assert cpu.negative == True
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = -1
instruction.exec(cpu, memory)
assert cpu.cycle == (instruction.cycles - 1)
assert cpu.y == 254
assert cpu.zero == False
assert cpu.negative == True
def test_DEY_within_bounds():
instruction = OpCodes.all[0x88]
cpu = CPU()
memory = Memory()
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 7
instruction.exec(cpu, memory)
assert cpu.cycle == (instruction.cycles - 1)
assert cpu.y == 6
assert cpu.zero == False
assert cpu.negative == False
def test_INY_zero():
instruction = OpCodes.all[0xC8]
cpu = CPU()
memory = Memory()
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = -1
instruction.exec(cpu, memory)
assert cpu.cycle == (instruction.cycles - 1)
assert cpu.y == 0
assert cpu.zero == True
assert cpu.negative == False
cpu.inc_cycle_by(-cpu.cycle)
cpu.y = 255
instruction.exec(cpu, memory)
assert cpu.cycle == (instruction.cycles - 1)
assert cpu.y == 0
assert cpu.zero == True
assert cpu.negative == False