ardupilot/libraries/AP_HAL/utility/st24.h

61 lines
2.8 KiB
C

// -*- tab-width: 8; Mode: C++; c-basic-offset: 8; indent-tabs-mode: -*- t -*-
/*
st24 decoder, based on PX4Firmware/src/rc/lib/rc/st24.c from PX4Firmware
modified for use in AP_HAL_* by Andrew Tridgell
*/
/****************************************************************************
*
* Copyright (c) 2014 PX4 Development Team. All rights reserved.
*
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*
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/**
* @file st24.h
*
* RC protocol definition for Yuneec ST24 transmitter
*
* @author Lorenz Meier <lm@inf.ethz.ch>
*/
#pragma once
/**
* Decoder for ST24 protocol
*
* @param byte current char to read
* @param rssi pointer to a byte where the RSSI value is written back to
* @param rx_count pointer to a byte where the receive count of packets signce last wireless frame is written back to
* @param channels pointer to a datastructure of size max_chan_count where channel values (12 bit) are written back to
* @param max_chan_count maximum channels to decode - if more channels are decoded, the last n are skipped and success (0) is returned
* @return 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
*/
int st24_decode(uint8_t byte, uint8_t *rssi, uint8_t *rx_count, uint16_t *channel_count,
uint16_t *channels, uint16_t max_chan_count);