epsflasher

#!/usr/bin/env python

import dirty4
import argparse
import rcx
import sys
import os
import time
import logging

# optional, non-core modules
try:
    import tqdm
except:
    pass

try:
    import colorlog
except:
    colorlog = logging

parser = argparse.ArgumentParser(description='Flash a firmware to an Epson printer.')
parser.add_argument('filename', metavar='firmware.rcx',
                    help='file to flash (RCX format)')
parser.add_argument('--device', default='/dev/usb/lp0',
                    help='printer to flash')
parser.add_argument('-d', '--debug', action='store_true',
                    help='output lots of debug spam')
parser.add_argument('--only-first-block', action='store_true',
                    help='only write the first firmware block; useful when the printer is in recovery mode')
args = parser.parse_args()

log_level = logging.INFO
if args.debug:
    log_level = logging.DEBUG

logformat = '%(levelname)-8s %(message)s'
if colorlog != logging:
    logformat = '%(log_color)s' + logformat
colorlog.basicConfig(level=log_level, format=logformat)

rcx_content = open(args.filename, 'rb').read()
header_len, cfg = rcx.parse_rcx(rcx_content)

block_sizes = []
for name, section in cfg.items():
    if name.startswith('Z_'):
        block_sizes.append(int(section['5']))

firmware_blob = rcx_content[header_len:]

if len(firmware_blob) != sum(block_sizes):
    logging.error("Firmware blob is %d bytes long but the header suggests %d" % (len(firmware_blob), sum(block_sizes)))
    sys.exit(1)

if args.only_first_block:
    firmware_blob = firmware_blob[:block_sizes[0]]

def strip_pref_suff(string, prefix, suffix=';\f'):
    if not string.startswith(prefix):
        logging.error("Unexpected response %s does not start with %s" % (repr(string), repr(prefix)))
        sys.exit(1)

    if not string.endswith(suffix):
        logging.error("Unexpected response %s does not end with %s" % (repr(string), repr(suffix)))
        sys.exit(1)

    return string[len(prefix):-len(suffix)]

port = os.open(args.device, os.O_RDWR | os.O_SYNC)
d4 = dirty4.Dirty4(port)

with d4.channel("EPSON-CTRL") as chan:
    version_info = strip_pref_suff(chan.cmd2('vi', 4), 'vi:04:')
    logging.info("Original firmware version: '%s'" % version_info)

    strip_pref_suff(chan.cmd2('fl', 1), 'fl:')

    gm_stat = strip_pref_suff(chan.cmd2('gm', 1), 'fl:01:')

    if gm_stat != 'OK':
        logging.error("Entering firmware download mode returned status '%s'" % gm_stat)
        sys.exit(1)

logging.info("Writing firmware...")

progress = None
try:
    bar = tqdm.tqdm(total=len(firmware_blob), unit='byte', unit_scale=True, unit_divisor=1024)
    def progress(increment):
        bar.update(increment)
except:
    pass

with d4.channel("EPSON-DATA") as chan:
    chan.write(firmware_blob, progress=progress)

if progress:
    bar.close()

with d4.channel("EPSON-CTRL") as chan:
    gm_stat = strip_pref_suff(chan.cmd2('gm', 3), 'fl:03:')

    if gm_stat != 'OK':
        logging.warning("Leaving firmware download mode returned status '%s'" % gm_stat)
        sys.exit(1)

logging.info("Waiting for printer to go away...")
try:
    while True:
        os.read(port, 1024)
        time.sleep(0.1)
except OSError:
    pass

os.close(port)

logging.info("Waiting for printer to come back...")
while True:
    try:
        port = os.open(args.device, os.O_RDWR | os.O_SYNC)
        break
    except OSError:
        time.sleep(1)

d4 = dirty4.Dirty4(port)

logging.info("Waiting for printer to be ready...")
with d4.channel("EPSON-CTRL") as chan:
    while True:
        version_info = strip_pref_suff(chan.cmd2('vi', 4), 'vi:04:')

        if version_info != 'BUSY':
            break

        time.sleep(1)

logging.info("OK. New firmware version: '%s'" % version_info)