A MOS 6502 Emulator intended to be used from within other programs. All opcodes, included the undocumented illegal opcodes are implemented.
Example Usage::
from py65emu import CPU, MMU
f = open("program.rom", "rb") # Open your rom
# define your blocks of memory. Each tuple is
# (start_address, length, readonly=True, initial_value=None, value_offset=0)
m = MMU([
(0x00, 0x200), # Create RAM with 512 bytes
(0x1000, 0x4000, True, f) # Create ROM starting at 0x1000 with your program.
])
# Create the CPU with the MMU and the starting program counter address
# You can also optionally pass in a value for stack_page, which defaults
# to 1, meaning the stack will be from 0x100-0x1ff. As far as I know this
# is true for all 6502s, but for instance in the 6507 used by the Atari
# 2600 it is in the zero page, stack_page=0.
c = CPU(mmu, 0x1000)
# Do this to execute one instruction
c.step()
# You can check the registers and memory values to determine what has changed
print(c.r.a) # A register
print(c.r.x) # X register
print(c.r.y) # Y register
print(c.r.s) # Stack Pointer
print(c.r.pc) # Program Counter
print(c.r.getFlag('C')) # Get the value of a flag from the flag register.
print(mmu.read(0xff)) # Read a value from memory