st24.h File Reference

RC protocol definition for Yuneec ST24 transmitter. More...

#include <stdint.h>

Go to the source code of this file.

Classes
struct	ReceiverFcPacket
struct	ChannelData12
	RC Channel data (12 channels). More...
struct	ChannelData24
	RC Channel data (12 channels). More...
struct	TelemetryData
	Telemetry packet. More...

Macros
#define	ST24_DATA_LEN_MAX   64
#define	ST24_STX1   0x55
#define	ST24_STX2   0x55

Enumerations
enum	ST24_PACKET_TYPE { ST24_PACKET_TYPE_CHANNELDATA12 = 0, ST24_PACKET_TYPE_CHANNELDATA24, ST24_PACKET_TYPE_TRANSMITTERGPSDATA }
enum	ST24_DECODE_STATE {   ST24_DECODE_STATE_UNSYNCED = 0, ST24_DECODE_STATE_GOT_STX1, ST24_DECODE_STATE_GOT_STX2, ST24_DECODE_STATE_GOT_LEN,   ST24_DECODE_STATE_GOT_TYPE, ST24_DECODE_STATE_GOT_DATA }

Functions
uint8_t	st24_common_crc8 (uint8_t *ptr, uint8_t len)
	CRC8 implementation for ST24 protocol. More...
__EXPORT int	st24_decode (uint8_t byte, uint8_t *rssi, uint8_t *lost_count, uint16_t *channel_count, uint16_t *channels, uint16_t max_chan_count)
	Decoder for ST24 protocol. More...

Detailed Description

RC protocol definition for Yuneec ST24 transmitter.

Author

Lorenz Meier lm@in.nosp@m.f.et.nosp@m.hz.ch

Function Documentation

st24_common_crc8()

uint8_t st24_common_crc8	(	uint8_t *	ptr,
		uint8_t	len
	)

CRC8 implementation for ST24 protocol.

Parameters

prt	Pointer to the data to CRC
len	number of bytes to accumulate in the checksum

Returns

the checksum of these bytes over len

st24_decode()

__EXPORT int st24_decode	(	uint8_t	byte,
		uint8_t *	rssi,
		uint8_t *	lost_count,
		uint16_t *	channel_count,
		uint16_t *	channels,
		uint16_t	max_chan_count
	)

Decoder for ST24 protocol.

Parameters

byte	current char to read
rssi	pointer to a byte where the RSSI value is written back to
lost_count	pointer to a byte where the receive count of packets since last wireless frame is written back to ( > 0 if RC is lost)
channels	pointer to a datastructure of size max_chan_count where channel values (12 bit) are written back to
max_chan_count	maximum channels to decode - if more channels are decoded, the last n are skipped and success (0) is returned

Returns

0 for success (a decoded packet), 1 for no packet yet (accumulating), 2 for unknown packet, 3 for out of sync, 4 for checksum error