ardupilot/libraries/AP_RCProtocol/AP_RCProtocol_SRXL2.cpp

460 lines
16 KiB
C++

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
SRXL2 protocol decoder using Horizon Hobby's open source library https://github.com/SpektrumRC/SRXL2
Code by Andy Piper
*/
#include "AP_RCProtocol.h"
#include "AP_RCProtocol_SRXL2.h"
#include <AP_Math/AP_Math.h>
#include <AP_RCTelemetry/AP_Spektrum_Telem.h>
#include <AP_Vehicle/AP_Vehicle_Type.h>
#include <AP_HAL/utility/sparse-endian.h>
#include <AP_RCTelemetry/AP_VideoTX.h>
#include "spm_srxl.h"
extern const AP_HAL::HAL& hal;
//#define SRXL2_DEBUG
#ifdef SRXL2_DEBUG
# define debug(fmt, args...) hal.console->printf("SRXL2:" fmt "\n", ##args)
#else
# define debug(fmt, args...) do {} while(0)
#endif
AP_RCProtocol_SRXL2* AP_RCProtocol_SRXL2::_singleton;
AP_RCProtocol_SRXL2::AP_RCProtocol_SRXL2(AP_RCProtocol &_frontend) : AP_RCProtocol_Backend(_frontend)
{
#if !APM_BUILD_TYPE(APM_BUILD_UNKNOWN)
if (_singleton != nullptr) {
AP_HAL::panic("Duplicate SRXL2 handler\n");
}
_singleton = this;
#else
if (_singleton == nullptr) {
_singleton = this;
}
#endif
}
void AP_RCProtocol_SRXL2::_bootstrap(uint8_t device_id)
{
if (_device_id == device_id) {
return;
}
// Init the local SRXL device
if (!srxlInitDevice(device_id, SRXL_DEVICE_PRIORITY, SRXL_DEVICE_INFO, device_id)) {
AP_HAL::panic("Failed to initialize SRXL2 device\n");
}
// Init the SRXL bus: The bus index must always be < SRXL_NUM_OF_BUSES -- in this case, it can only be 0
if (!srxlInitBus(0, 0, SRXL_SUPPORTED_BAUD_RATES)) {
AP_HAL::panic("Failed to initialize SRXL2 bus\n");
}
_device_id = device_id;
debug("Bootstrapped as 0x%x", _device_id);
}
AP_RCProtocol_SRXL2::~AP_RCProtocol_SRXL2() {
_singleton = nullptr;
}
void AP_RCProtocol_SRXL2::_process_byte(uint32_t timestamp_us, uint8_t byte)
{
if (_decode_state == STATE_IDLE) {
switch (byte) {
case SPEKTRUM_SRXL_ID:
_decode_state = STATE_NEW;
break;
default:
_decode_state = STATE_IDLE;
return;
}
_frame_len_full = 0U;
_buflen = 0;
_decode_state_next = STATE_IDLE;
}
switch (_decode_state) {
case STATE_NEW: // buffer header byte and prepare for frame reception and decoding
_buffer[0U]=byte;
_buflen = 1U;
_decode_state_next = STATE_COLLECT;
break;
case STATE_COLLECT: // receive all bytes. After reception decode frame and provide rc channel information to FMU
_buffer[_buflen] = byte;
_buflen++;
// need a header to get the length
if (_buflen < SRXL2_HEADER_LEN) {
return;
}
// parse the length
if (_buflen == SRXL2_HEADER_LEN) {
_frame_len_full = _buffer[2];
// check for garbage frame
if (_frame_len_full > SRXL2_FRAMELEN_MAX) {
_decode_state = STATE_IDLE;
_buflen = 0;
_frame_len_full = 0;
}
return;
}
if (_buflen > _frame_len_full) {
// a logic bug in the state machine, this shouldn't happen
_decode_state = STATE_IDLE;
_buflen = 0;
_frame_len_full = 0;
return;
}
if (_buflen == _frame_len_full) {
log_data(AP_RCProtocol::SRXL2, timestamp_us, _buffer, _buflen);
// we got a full frame but never handshaked before
if (!is_bootstrapped()) {
if (_buffer[1] == 0x21) {
_bootstrap(SRXL_DEVICE_ID);
_last_handshake_ms = timestamp_us / 1000;
} else {
// not a handshake frame so reset without initializing the SRXL2 engine
_decode_state = STATE_IDLE;
_buflen = 0;
_frame_len_full = 0;
return;
}
}
// Try to parse SRXL packet -- this internally calls srxlRun() after packet is parsed and resets timeout
if (srxlParsePacket(0, _buffer, _frame_len_full)) {
add_input(MAX_CHANNELS, _channels, _in_failsafe, _new_rssi);
}
_last_run_ms = AP_HAL::millis();
_decode_state_next = STATE_IDLE;
_buflen = 0;
} else {
_decode_state_next = STATE_COLLECT;
}
break;
default:
break;
}
_decode_state = _decode_state_next;
}
void AP_RCProtocol_SRXL2::update(void)
{
// on a SPM4650 with telemetry the frame rate is 91Hz equating to around 10ms per frame
// however only half of them can return telemetry, so the maximum telemetry rate is 46Hz
// also update() is run immediately after check_added_uart() and so in general the delay is < 5ms
// to be safe we will only run if the timeout exceeds 50ms
if (_last_run_ms > 0) {
uint32_t now = AP_HAL::millis();
// there have been no updates since we were last called
const uint32_t delay = now - _last_run_ms;
if (delay > 50) {
srxlRun(0, delay);
_last_run_ms = now;
}
}
}
void AP_RCProtocol_SRXL2::capture_scaled_input(const uint8_t *values_p, bool in_failsafe, int16_t new_rssi)
{
AP_RCProtocol_SRXL2* srxl2 = AP_RCProtocol_SRXL2::get_singleton();
if (srxl2 != nullptr) {
srxl2->_capture_scaled_input(values_p, in_failsafe, new_rssi);
}
}
// capture SRXL2 encoded values
void AP_RCProtocol_SRXL2::_capture_scaled_input(const uint8_t *values_p, bool in_failsafe, int16_t new_rssi)
{
_in_failsafe = in_failsafe;
// AP rssi: -1 for unknown, 0 for no link, 255 for maximum link
// SRXL2 rssi: -ve rssi in dBM, +ve rssi in percentage
if (new_rssi >= 0) {
_new_rssi = new_rssi * 255 / 100;
}
for (uint8_t i = 0; i < MAX_CHANNELS; i++) {
/*
* Store the decoded channel into the R/C input buffer, taking into
* account the different ideas about channel assignement that we have.
*
* Specifically, the first four channels in rc_channel_data are roll, pitch, thrust, yaw,
* but the first four channels from the DSM receiver are thrust, roll, pitch, yaw.
*/
uint8_t channel = i;
switch (channel) {
case 0:
channel = 2;
break;
case 1:
channel = 0;
break;
case 2:
channel = 1;
break;
default:
break;
}
/*
* Each channel data value is sent as an unsigned 16-bit value from 0 to 65532 (0xFFFC)
* with 32768 (0x8000) representing "Servo Center". The channel value must be bit-shifted
* to the right to match the applications's accepted resolution.
*
* So here we scale to DSMX-2048 and then use our regular Spektrum conversion.
*/
const uint16_t v = le16toh_ptr(&values_p[i*2]);
_channels[channel] = ((int32_t)(v >> 5) * 1194) / 2048 + 903;
}
}
// start bind on DSM satellites
void AP_RCProtocol_SRXL2::start_bind(void)
{
srxlEnterBind(DSMX_11MS, true);
}
// process a byte provided by a uart
void AP_RCProtocol_SRXL2::process_byte(uint8_t byte, uint32_t baudrate)
{
if (baudrate != 115200) {
return;
}
_process_byte(AP_HAL::micros(), byte);
}
// handshake
void AP_RCProtocol_SRXL2::process_handshake(uint32_t baudrate)
{
// only bootstrap if only SRXL2 is enabled
if (baudrate != 115200 || (get_rc_protocols_mask() & ~(1U<<(uint8_t(AP_RCProtocol::SRXL2)+1)))) {
_handshake_start_ms = 0;
return;
}
uint32_t now = AP_HAL::millis();
// record the time of the first request in this cycle
if (_handshake_start_ms == 0) {
_handshake_start_ms = now;
// it seems the handshake protocol only sets the baudrate after receiving data
// since we are sending data unprompted make sure that the uart is set up correctly
_change_baud_rate(baudrate);
}
// we have not bootstrapped and attempts to listen first have failed
// we should receive a handshake request within the first 250ms
if (!is_bootstrapped() && now - _handshake_start_ms > 250) {
_bootstrap(SRXL_DEVICE_ID_BASE_RX);
}
// certain RXs (e.g. AR620) are "listen-only" - they require the flight controller to initiate
// a handshake in order to switch to SRXL2 mode. This requires that we send data on the UART even
// if we have not decoded SRXL2 (recently). We try this every 50ms.
if (now - _handshake_start_ms > 250 && (_last_handshake_ms == 0 || (now - _last_run_ms > 50 && now - _last_handshake_ms > 50))) {
_in_bootstrap_or_failsafe = true;
srxlRun(0, 50); // 50 is a magic number at which the handshake protocol is initiated
_in_bootstrap_or_failsafe = false;
_last_handshake_ms = now;
}
}
// send data to the uart
void AP_RCProtocol_SRXL2::send_on_uart(uint8_t* pBuffer, uint8_t length)
{
AP_RCProtocol_SRXL2* srxl2 = AP_RCProtocol_SRXL2::get_singleton();
if (srxl2 != nullptr) {
srxl2->_send_on_uart(pBuffer, length);
}
}
// configure the video transmitter, the input values are Spektrum-oriented
void AP_RCProtocol_SRXL2::configure_vtx(uint8_t band, uint8_t channel, uint8_t power, uint8_t pitmode)
{
AP_VideoTX& vtx = AP::vtx();
// VTX Band (0 = Fatshark, 1 = Raceband, 2 = E, 3 = B, 4 = A)
// map to TBS band A, B, E, Race, Airwave, LoRace
switch (band) {
case VTX_BAND_FATSHARK:
vtx.set_configured_band(AP_VideoTX::VideoBand::FATSHARK);
break;
case VTX_BAND_RACEBAND:
vtx.set_configured_band(AP_VideoTX::VideoBand::RACEBAND);
break;
case VTX_BAND_E_BAND:
vtx.set_configured_band(AP_VideoTX::VideoBand::BAND_E);
break;
case VTX_BAND_B_BAND:
vtx.set_configured_band(AP_VideoTX::VideoBand::BAND_B);
break;
case VTX_BAND_A_BAND:
vtx.set_configured_band(AP_VideoTX::VideoBand::BAND_A);
break;
default:
break;
}
// VTX Channel (0-7)
vtx.set_configured_channel(channel);
if (pitmode) {
vtx.set_configured_options(vtx.get_options() | uint8_t(AP_VideoTX::VideoOptions::VTX_PITMODE));
} else {
vtx.set_configured_options(vtx.get_options() & ~uint8_t(AP_VideoTX::VideoOptions::VTX_PITMODE));
}
switch (power) {
case VTX_POWER_1MW_14MW:
case VTX_POWER_15MW_25MW:
vtx.set_configured_power_mw(25);
break;
case VTX_POWER_26MW_99MW:
case VTX_POWER_100MW_299MW:
vtx.set_configured_power_mw(100);
break;
case VTX_POWER_300MW_600MW:
vtx.set_configured_power_mw(400);
break;
case VTX_POWER_601_PLUS:
vtx.set_configured_power_mw(800);
break;
default:
break;
}
}
// send data to the uart
void AP_RCProtocol_SRXL2::_send_on_uart(uint8_t* pBuffer, uint8_t length)
{
AP_HAL::UARTDriver* uart = get_available_UART();
if (uart != nullptr && uart->is_initialized()) {
// check that we haven't been too slow in responding to the new UART data. If we respond too late then we will
// corrupt the next incoming control frame. incoming packets at max 800bits @91Hz @115k baud gives total budget of 11ms
// per packet of which we need 7ms to receive a packet. outgoing packets are 220 bits which require 2ms to send
// leaving at most 2ms of delay that can be tolerated
uint64_t tend = uart->receive_time_constraint_us(1);
uint64_t now = AP_HAL::micros64();
uint64_t tdelay = now - tend;
if (tdelay > 2000 && !_in_bootstrap_or_failsafe) {
// we've been too slow in responding
return;
}
// debug telemetry packets
if (pBuffer[1] == 0x80 && pBuffer[4] != 0) {
debug("0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x: %s",
pBuffer[0], pBuffer[1], pBuffer[2], pBuffer[3], pBuffer[4], pBuffer[5], pBuffer[6], pBuffer[7], pBuffer[8], pBuffer[9], &pBuffer[7]);
}
uart->write(pBuffer, length);
}
}
// change the uart baud rate
void AP_RCProtocol_SRXL2::change_baud_rate(uint32_t baudrate)
{
AP_RCProtocol_SRXL2* srxl2 = AP_RCProtocol_SRXL2::get_singleton();
if (srxl2 != nullptr) {
srxl2->_change_baud_rate(baudrate);
}
}
// change the uart baud rate
void AP_RCProtocol_SRXL2::_change_baud_rate(uint32_t baudrate)
{
AP_HAL::UARTDriver* uart = get_available_UART();
if (uart != nullptr) {
uart->begin(baudrate);
uart->set_flow_control(AP_HAL::UARTDriver::FLOW_CONTROL_DISABLE);
uart->set_unbuffered_writes(true);
uart->set_blocking_writes(false);
}
}
// SRXL2 library callbacks below
// User-provided routine to change the baud rate settings on the given UART:
// uart - the same uint8_t value as the uart parameter passed to srxlInit()
// baudRate - the actual baud rate (currently either 115200 or 400000)
void srxlChangeBaudRate(uint8_t uart, uint32_t baudRate)
{
AP_RCProtocol_SRXL2::change_baud_rate(baudRate);
}
// User-provided routine to actually transmit a packet on the given UART:
// uart - the same uint8_t value as the uart parameter passed to srxlInit()
// pBuffer - a pointer to an array of uint8_t values to send over the UART
// length - the number of bytes contained in pBuffer that should be sent
void srxlSendOnUart(uint8_t uart, uint8_t* pBuffer, uint8_t length)
{
AP_RCProtocol_SRXL2::send_on_uart(pBuffer, length);
}
// User-provided callback routine to fill in the telemetry data to send to the master when requested:
// pTelemetryData - a pointer to the 16-byte SrxlTelemetryData transmit buffer to populate
// NOTE: srxlTelemData is available as a global variable, so the memcpy line commented out below
// could be used if you would prefer to just populate that with the next outgoing telemetry packet.
void srxlFillTelemetry(SrxlTelemetryData* pTelemetryData)
{
#if HAL_SPEKTRUM_TELEM_ENABLED && !APM_BUILD_TYPE(APM_BUILD_iofirmware)
AP_Spektrum_Telem::get_telem_data(pTelemetryData->raw);
#endif
}
// User-provided callback routine that is called whenever a control data packet is received:
// pChannelData - a pointer to the received SrxlChannelData structure for manual parsing
// isFailsafe - true if channel data is set to failsafe values, else false.
// this is called from within srxlParsePacket() and before the SRXL2 state machine has been run
// so be very careful to only do local operations
void srxlReceivedChannelData(SrxlChannelData* pChannelData, bool isFailsafe)
{
if (isFailsafe) {
AP_RCProtocol_SRXL2::capture_scaled_input((const uint8_t *)pChannelData->values, true, pChannelData->rssi);
} else {
AP_RCProtocol_SRXL2::capture_scaled_input((const uint8_t *)srxlChData.values, false, srxlChData.rssi);
}
}
// User-provided callback routine to handle reception of a bound data report (either requested or unprompted).
// Return true if you want this bind information set automatically for all other receivers on all SRXL buses.
bool srxlOnBind(SrxlFullID device, SrxlBindData info)
{
return true;
}
// User-provided callback routine to handle reception of a VTX control packet.
void srxlOnVtx(SrxlVtxData* pVtxData)
{
AP_RCProtocol_SRXL2::configure_vtx(pVtxData->band, pVtxData->channel, pVtxData->power, pVtxData->pit);
}