mirror of https://github.com/ArduPilot/ardupilot
33 lines
1.2 KiB
C
33 lines
1.2 KiB
C
#pragma once
|
|
#include "AP_Frsky_Backend.h"
|
|
|
|
/*
|
|
|
|
Wire Protocol:
|
|
|
|
Several SPort packets make up a MAVlite message.
|
|
|
|
A maximum of six relevant data bytes are present in an SPort packet.
|
|
|
|
Each SPort packet starts with a sequence number, starting with zero.
|
|
|
|
If the sequence number is zero then the parser is reset.
|
|
|
|
The first sport packet contains len at offset 1. It is the
|
|
*payload* length - does not include checksum, for example. msgid is
|
|
at offset 2, then payload bytes.
|
|
|
|
Subsequent SPort packets contain a sequence number at offset zero,
|
|
followed by more payload bytes.
|
|
|
|
When sufficient payload bytes have been received (based on "len"), a
|
|
single checksum byte arrives. Sometimes this checksum byte goes
|
|
into an SPort packet all on its own, sharing space only with the
|
|
sequence number.
|
|
|
|
*/
|
|
|
|
#define MAVLITE_MAX_PAYLOAD_LEN 31 // 7 float params + cmd_id + options
|
|
#define MAVLITE_MSG_SPORT_PACKETS_COUNT(LEN) static_cast<uint8_t>(1 + ceilf((LEN-2)/5.0f)) // number of sport packets required to transport a message with LEN payload
|
|
#define SPORT_PACKET_QUEUE_LENGTH static_cast<uint8_t>(30U*MAVLITE_MSG_SPORT_PACKETS_COUNT(MAVLITE_MAX_PAYLOAD_LEN))
|