enum{ RECEIVING, NOT_RECEIVING }; enum{ AM_PULSE=194, AM_SENSITIVITYMSG=195, AM_TOF=196, AM_CHIRPMSG=197, AM_TRANSMITMODEMSG=199, AM_TIMESTAMPMSG=198 }; enum{ LEN_CHIRPMSG=2, LEN_TRANSMITMODEMSG=1, LEN_TIMESTAMPMSG=4 }; enum{TRANSMIT,RECEIVE}; typedef struct TransmitModeMsg{ uint8_t mode; } TransmitModeMsg; typedef struct TimestampMsg{ uint16_t transmitterId; uint16_t timestamp; } TimestampMsg; typedef struct ChirpMsg{ uint16_t transmitterId; } ChirpMsg;