dump from CMS 50F 3.7 v0.2

#!/usr/bin/python
# -*- coding: UTF-8 -*-
# Contec CMS 50F firmware 3.7 dumper
# (C) 2014, François Revol <revol@free.fr>

#cf. http://elinux.org/Serial_port_programming

import serial
import sys
import time


def send_cmd(p, c):
	print "> %s" % c
	c = c.replace(' ', '')
	c = c.decode("hex")
	#print c.encode("hex")
	p.write(c)
	#p.flush()

def recv_data(p, l=None):
	data = ''
	while l is None or len(data) < l:
		time.sleep(0.5)
		if p.inWaiting() < 1:
			print "No more data..."
			# XXX: do something?
			if l is None:
				break
		want = max(p.inWaiting(), 1)
		if l is not None:
			want = min(want, l - len(data))
		# just for nicer hex dump, wrap at 8 bytes
		want = min(want, 8)
		#print len
		d = p.read(want)
		hx = d.encode("hex")
		print "< %s" % " ".join(hx[i:i+2] for i in range(0, len(hx), 2))
		data += d
	print
	return data

if len(sys.argv) < 2:
	print "Usage: %s serialdev" % sys.argv[0]
	exit(1)

#, parity=serial.PARITY_ODD
with serial.Serial(port=sys.argv[1], baudrate=115200) as p:
	send_cmd(p, '7d 81 a7 80 80 80 80 80 80')
	recv_data(p, 2)
	send_cmd(p, '7d 81 a2 80 80 80 80 80 80')
	recv_data(p, 2)
	send_cmd(p, '7d 81 a0 80 80 80 80 80 80')
	recv_data(p, 4)

	send_cmd(p, '7d 81 b0 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 ac 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 b3 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 ad 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 a3 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 ab 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 a4 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 a5 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 af 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 a7 80 80 80 80 80 80')
	recv_data(p)

	send_cmd(p, '7d 81 a2 80 80 80 80 80 80')
	recv_data(p)


	send_cmd(p, '7d 81 a6 80 80 80 80 80 80')
	recv_data(p)