self.gps_nb_sat = payload[6] & 0x0F
lat, lon, speed, flags = unpack("!IIBH", payload[7:18])
self.gps_is_valid = bool(flags & 0b0001000000000000) # bit 3
self.gps_nb_sat = payload[6] & 0x0F
lat, lon, speed, flags = unpack("!IIBH", payload[7:18])
self.gps_is_valid = bool(flags & 0b0001000000000000) # bit 3