Connects to mame's network socket, grabs 573 lighting info, writes it to the piuio using djpohly's kernel driver.

mame2piuio.py

#!/usr/bin/env python

# =============================================================================
# Author: din
# Requirements: Linux and mame-git
# Description: Set mame "output" option in mame.ini to "network" and then 
#              run this script after launching mame.
# =============================================================================

import socket
import os
import time

PIUIO_OUTPUT_LOCATION = "/sys/class/leds/piuio::output{}/brightness"

#mame name: piuio output number
light_order = {
    "foot 1p left": 20,
    "foot 1p right": 21,
    "foot 1p up": 18,
    "foot 1p down": 19,

    "foot 2p left": 4,
    "foot 2p right": 5,
    "foot 2p up": 2,
    "foot 2p down": 3,

    "body right high": 26,
    "body right low": 24,
    "body left high":  23,
    "body left low": 25 ,

    #PIUIO doesn't have the player button lights.
    #"lamp0": 0,
    #"lamp1": 0,

    "speaker": 10,
}

def set_piuio_light(light_num, state):
    light_loc = PIUIO_OUTPUT_LOCATION.format(light_num)
    #print(light_loc, " > ", state)

    try:
        os_file = os.open(light_loc,os.O_RDWR)
        os.write(os_file, b"%d\n" % int(state))
        os.close(os_file)
    except:
        #print("Could not update light state to PIUIO")
        pass
        
def decode_mame_light(recv_string):
    light_state = recv_string.split(' = ')
    
    try:
        set_piuio_light(light_order[light_state[0]], light_state[1])
    except KeyError:
        #print("Unknown light: ", light_state[0])
        pass

mame_line = ''
printed_error_msg = False

while 1:
    try:
        #mame statically defines a network port of 8000 to connect to.
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.connect(("localhost", 8000))
        
        print("\r\nConnected.")
        print("Writing MAME lighting state to PIUIO...")
        
        while 1:
            char = s.recv(1)
            
            #buffer up an entire line until we see a carrage return
            if char == b'\r':
                decode_mame_light(mame_line)
                mame_line = ''
            else:
                mame_line += char[0:1].decode("utf-8")
    except KeyboardInterrupt:
        break
    except:
        if not printed_error_msg:
            print("Connection to mame failed, trying again.", end='', flush=True)
            printed_error_msg = True
        else:
            print('.', end='', flush=True)
            
        time.sleep(0.5)