cpu 6502 test

root@raspberrypi:~# cat ./cpu6502.py 
#!/usr/bin/env python
"""
run as root :)
"""
import RPi.GPIO as GPIO
import signal, sys, os, time

GPIO.setmode(GPIO.BCM)


ADDRESS_PINS = [
    4, 17, 27, 22, 10, 9, 11, 5, 6, 13, 19, 26, 21, 20, 16, 12 
]

RESET_PIN = 8
CLOCK_PIN = 7


def terminate(signum, frame):
    GPIO.cleanup()      
    sys.exit(0)

def setup():
    # Address pins
    for pin in ADDRESS_PINS:
        GPIO.setup(pin, GPIO.IN, pull_up_down = GPIO.PUD_DOWN)

    # Reset pin
    GPIO.setup(RESET_PIN, GPIO.OUT)

    # Clock PIN (PHI2)
    GPIO.setup(CLOCK_PIN, GPIO.OUT)

    # SIGINT
    signal.signal(signal.SIGINT, terminate)


def reset():
    GPIO.output(RESET_PIN, GPIO.HIGH)
    time.sleep(0.1)
    GPIO.output(RESET_PIN, GPIO.LOW)
    time.sleep(0.1)
    GPIO.output(RESET_PIN, GPIO.HIGH)
    print("reset complete")


def send_clock():
    time.sleep(0.1)
    GPIO.output(CLOCK_PIN, GPIO.LOW)
    time.sleep(0.1)
    GPIO.output(CLOCK_PIN, GPIO.HIGH)


def read_address():
    pin_state = ""
    for pin in reversed(ADDRESS_PINS):
        pin_state += str(GPIO.input(pin))

    hex_address = hex(int(pin_state, 2))
    return pin_state, hex_address


def main_loop():
    while True:
        address = read_address()

        input = None
        #input = raw_input('("reset", (n)ext, "(r)ead"  [{}]> '.format(address))

        if input == "reset":
            reset()
        elif input == "r":
            print("READ!: [{}]".format(read_address()))

        else:
            print("READ!: [{}]".format(read_address()))
            send_clock()
        

if __name__ == "__main__":
    setup()
    reset()
    main_loop()