import time
import serial

port = serial.Serial("/dev/ttyUSB0", 2400)

def decode_packet(bytes):
	value = (ord(bytes[2]) << 16) | (ord(bytes[1]) << 8) | ord(bytes[0])
	
	first = value & 0x555555
	second = ((value & 0xAAAAAA) >> 1) ^ 0x555555
	
	if first != second:
		return None
	
	result = 0
	for i in range(12):
		if first & (1 << (i * 2)):
			result |= (1 << i);
	
	return result

packets = []
start = time.time()
prevtime = start
prev_packet = start

while True:
	byte = port.read(1)
	
	if byte == '\xCC':
		packet = port.read(3)
		#print "Got CC", ' '.join([hex(ord(c)) for c in packet])
		if decode_packet(packet) is not None:
			packets.append(packet)
			packets = packets[-16:]
			prev_packet = time.time()
	
	if time.time() - prev_packet > 0.1:
		if packets and packets.count(packets[-1]) >= 2:
			packet = packets[-1]
			count = packets.count(packet)
			packets = []
			temp = decode_packet(packet)
			
			if time.time() - prevtime > 0.2:
				print '\r', "%5d" % int(time.time() - start), "%02.2f" % (temp / 16.0), "\t", count, "       "
				prevtime = time.time()
	
	print '\r', "%5d" % (int(time.time() - prevtime)), len(packets),