from py65emu.cpu import CPU
    from py65emu.mmu import MMU

    f = open("program.rom", "rb")  # Open your rom

    # define your blocks of memory.  Each tuple is
    # (start_address, length, readOnly=True, value=None, valueOffset=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.cc)     # Print the number of cycles that passed during the last step.
                    # This number resets for each call to `.step()`

    print(c.r.getFlag('C')) # Get the value of a flag from the flag register.

    print(mmu.read(0xff)) # Read a value from memory

    mmu: An instance of MMU
    pc: The starting address of the pc (program counter)
    stack_page: The index of the page which contains the stack.  The default for
        a 6502 is page 1 (the stack from 0x0100-0x1ff) but in some varients the
        stack page may be elsewhere.
    magic: A value needed for the illegal opcodes, XAA.  This value differs
        between different versions, even of the same CPU.  The default is 0xee.

    start : int
        The starting address of the block of memory
    length : int
        The length of the block in bytes
    readOnly: bool
        Whether the block should be read only (such as ROM) (default False)
    value : file pointer, binary or lint of unsigned integers
        The intial value for the block of memory. Used for loading program
        data. (Default None)
    valueOffset : integer
        Used when copying the above `value` into the block to offset the
        location it is copied into. For example, to copy byte 0 in `value`
        into location 1000 in the block, set valueOffest=1000. (Default 0)