File syn_mavlink.h¶

FileList > proto > syn_mavlink.h

Zero-Heap MAVLink v2 Protocol Encoder & Streaming Decoder. More...

#include "syntropic/common/syn_defs.h"
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

Classes¶

Type	Name
struct	SYN_MAVLINK_Frame
struct	SYN_MAVLINK_Parser

Public Types¶

Type	Name
enum	SYN_MAVLINK_MsgId

Public Functions¶

Type	Name
uint16_t	syn_mavlink_crc_accumulate (uint8_t byte, uint16_t crc) Accumulate single byte into MAVLink X25 CRC.
SYN_Status	syn_mavlink_encode_msg (uint8_t sys_id, uint8_t comp_id, uint8_t seq, uint32_t msg_id, uint8_t crc_extra, const uint8_t * payload, uint8_t payload_len, uint8_t * buf_out, size_t * out_len) Encode a MAVLink v2 packet into raw byte buffer.
SYN_Status	syn_mavlink_init (SYN_MAVLINK_Parser * parser) Initialize MAVLink v2 parser instance.
SYN_Status	syn_mavlink_parse_byte (SYN_MAVLINK_Parser * parser, uint8_t byte, SYN_MAVLINK_Frame * frame) Process incoming byte from serial stream.

Macros¶

Type	Name
define	SYN_MAVLINK_HEADER_LEN `10U`
define	SYN_MAVLINK_MAX_PAYLOAD_LEN `255U`
define	SYN_MAVLINK_STX_V2 `0xFD`

Detailed Description¶

MAVLink v2 Frame Specification: Header: [0xFD] + [Payload Len 1B] + [Incompat Flags 1B] + [Compat Flags 1B] + [Seq 1B] + [Sys ID 1B] + [Comp ID 1B] + [Msg ID 3B (Little-Endian)] Payload: [Payload N B] Checksum: [16-bit CRC-X25 over (Header_without_STX + Payload + CRC_Extra)]

Public Types Documentation¶

enum SYN_MAVLINK_MsgId¶

enum SYN_MAVLINK_MsgId {
    SYN_MAVLINK_MSG_HEARTBEAT = 0U,
    SYN_MAVLINK_MSG_SYS_STATUS = 1U,
    SYN_MAVLINK_MSG_ATTITUDE = 30U,
    SYN_MAVLINK_MSG_GLOBAL_POSITION_INT = 33U,
    SYN_MAVLINK_MSG_VFR_HUD = 74U
};

MAVLink Message IDs.

Public Functions Documentation¶

function syn_mavlink_crc_accumulate¶

Accumulate single byte into MAVLink X25 CRC.

uint16_t syn_mavlink_crc_accumulate (
    uint8_t byte,
    uint16_t crc
)

Parameters:

byte Input byte to accumulate.
crc Initial CRC accumulator value.

Returns:

Updated 16-bit CRC value.

function syn_mavlink_encode_msg¶

Encode a MAVLink v2 packet into raw byte buffer.

SYN_Status syn_mavlink_encode_msg (
    uint8_t sys_id,
    uint8_t comp_id,
    uint8_t seq,
    uint32_t msg_id,
    uint8_t crc_extra,
    const uint8_t * payload,
    uint8_t payload_len,
    uint8_t * buf_out,
    size_t * out_len
)

Parameters:

sys_id System ID (1..255).
comp_id Component ID (1..255).
seq Packet sequence number.
msg_id Message ID.
crc_extra CRC Extra byte for the specific message ID.
payload Pointer to payload data buffer (or NULL if 0 len).
payload_len Payload byte length.
buf_out Output byte buffer (must hold at least payload_len + 12 bytes).
out_len Pointer to receive final encoded frame length.

Returns:

SYN_OK on success.

function syn_mavlink_init¶

Initialize MAVLink v2 parser instance.

SYN_Status syn_mavlink_init (
    SYN_MAVLINK_Parser * parser
)

Parameters:

parser Pointer to parser struct.

Returns:

SYN_OK on success.

function syn_mavlink_parse_byte¶

Process incoming byte from serial stream.

SYN_Status syn_mavlink_parse_byte (
    SYN_MAVLINK_Parser * parser,
    uint8_t byte,
    SYN_MAVLINK_Frame * frame
)

Parameters:

parser Pointer to parser struct.
byte Incoming byte.
frame Destination frame struct (populated on valid complete packet).

Returns:

SYN_OK on complete valid frame, SYN_BUSY if processing, SYN_ERROR on CRC mismatch.

Macro Definition Documentation¶

define SYN_MAVLINK_HEADER_LEN¶

#define SYN_MAVLINK_HEADER_LEN `10U`

MAVLink v2 header length in bytes

define SYN_MAVLINK_MAX_PAYLOAD_LEN¶

#define SYN_MAVLINK_MAX_PAYLOAD_LEN `255U`

Maximum MAVLink payload length in bytes

define SYN_MAVLINK_STX_V2¶

#define SYN_MAVLINK_STX_V2 `0xFD`

MAVLink v2 Start of Frame marker byte (0xFD)

The documentation for this class was generated from the following file src/syntropic/proto/syn_mavlink.h