def ALUMemHelper(f, opcode: bytes, cpu: CPU.CPU):
#find the addressing mode of this operation. The addressing mode for the ALU operations are stored in bit 2, 3 and 4.
code = (opcode & 0b11100) >> 2
#use the helper function to retrieve the byte from memory
print("Counter: " + str(cpu.PC))
print(cpu.instructions[0:100])
nextbytes = cpu.instructions[cpu.PC + 1:cpu.PC + 1 + 2]
try:
print("Next bytes: " + str(nextbytes[0]) + " : " + str(nextbytes[1]))
except:
print("Next bytes: " + str(nextbytes[0]))
print("code: " + str(code))
val = getMemArray[code](cpu, nextbytes)
print("Memory address to be accessed: " + str(val[0]))
cpu.PC += val[1]
if (code == 2):
val = cpu.instructions[val[0]:val[0] + 1]
else:
val = cpu.ram.read_bytes(val[0], 1)
print("Val retrieved from memory: " + str(val))
#perform the ALU operation on the retrieved byte
result = f(cpu.A, val[0])
print("Result: " + str(result))
#TODO: not sure of the exact functionality of the carry bit. Should it be cleared if no carry occurs in bit 7?
#set cpu flags
if not (opcode >> 7 == 1):
fresult = result % 256
carry = result > fresult
cpu.P = (cpu.P & 0b01111100) | carry | (
(fresult == 0) << 1) | (fresult & 0b10000000)
result = fresult
#save result to accumulator
cpu.A = result
