ardupilot/libraries/AP_GPS/AP_GPS_SBP.cpp

449 lines
14 KiB
C++

// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
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/>.
*/
//
// Swift Navigation SBP GPS driver for ArduPilot.
// Code by Niels Joubert
//
// Swift Binary Protocol format: http://docs.swift-nav.com/
//
#include "AP_GPS.h"
#include "AP_GPS_SBP.h"
#include <DataFlash/DataFlash.h>
extern const AP_HAL::HAL& hal;
#define SBP_DEBUGGING 1
#define SBP_HW_LOGGING 1
#define SBP_TIMEOUT_HEATBEAT 4000
#define SBP_TIMEOUT_PVT 500
#if SBP_DEBUGGING
# define Debug(fmt, args ...) \
do { \
hal.console->printf("%s:%d: " fmt "\n", \
__FUNCTION__, __LINE__, \
## args); \
hal.scheduler->delay(1); \
} while(0)
#else
# define Debug(fmt, args ...)
#endif
AP_GPS_SBP::AP_GPS_SBP(AP_GPS &_gps, AP_GPS::GPS_State &_state,
AP_HAL::UARTDriver *_port) :
AP_GPS_Backend(_gps, _state, _port),
last_injected_data_ms(0),
last_iar_num_hypotheses(0),
last_full_update_tow(0),
last_full_update_cpu_ms(0),
crc_error_counter(0)
{
Debug("SBP Driver Initialized");
parser_state.state = sbp_parser_state_t::WAITING;
//Externally visible state
state.status = AP_GPS::NO_FIX;
state.have_vertical_velocity = true;
state.last_gps_time_ms = last_heatbeat_received_ms = AP_HAL::millis();
}
// Process all bytes available from the stream
//
bool
AP_GPS_SBP::read(void)
{
//Invariant: Calling this function processes *all* data current in the UART buffer.
//
//IMPORTANT NOTICE: This function is NOT CALLED for several seconds
// during arming. That should not cause the driver to die. Process *all* waiting messages
_sbp_process();
return _attempt_state_update();
}
void
AP_GPS_SBP::inject_data(uint8_t *data, uint8_t len)
{
if (port->txspace() > len) {
last_injected_data_ms = AP_HAL::millis();
port->write(data, len);
} else {
Debug("PIKSI: Not enough TXSPACE");
}
}
//This attempts to reads all SBP messages from the incoming port.
//Returns true if a new message was read, false if we failed to read a message.
void
AP_GPS_SBP::_sbp_process()
{
while (port->available() > 0) {
uint8_t temp = port->read();
uint16_t crc;
//This switch reads one character at a time,
//parsing it into buffers until a full message is dispatched
switch(parser_state.state) {
case sbp_parser_state_t::WAITING:
if (temp == SBP_PREAMBLE) {
parser_state.n_read = 0;
parser_state.state = sbp_parser_state_t::GET_TYPE;
}
break;
case sbp_parser_state_t::GET_TYPE:
*((uint8_t*)&(parser_state.msg_type) + parser_state.n_read) = temp;
parser_state.n_read += 1;
if (parser_state.n_read >= 2) {
parser_state.n_read = 0;
parser_state.state = sbp_parser_state_t::GET_SENDER;
}
break;
case sbp_parser_state_t::GET_SENDER:
*((uint8_t*)&(parser_state.sender_id) + parser_state.n_read) = temp;
parser_state.n_read += 1;
if (parser_state.n_read >= 2) {
parser_state.n_read = 0;
parser_state.state = sbp_parser_state_t::GET_LEN;
}
break;
case sbp_parser_state_t::GET_LEN:
parser_state.msg_len = temp;
parser_state.n_read = 0;
parser_state.state = sbp_parser_state_t::GET_MSG;
break;
case sbp_parser_state_t::GET_MSG:
*((uint8_t*)&(parser_state.msg_buff) + parser_state.n_read) = temp;
parser_state.n_read += 1;
if (parser_state.n_read >= parser_state.msg_len) {
parser_state.n_read = 0;
parser_state.state = sbp_parser_state_t::GET_CRC;
}
break;
case sbp_parser_state_t::GET_CRC:
*((uint8_t*)&(parser_state.crc) + parser_state.n_read) = temp;
parser_state.n_read += 1;
if (parser_state.n_read >= 2) {
parser_state.state = sbp_parser_state_t::WAITING;
crc = crc16_ccitt((uint8_t*)&(parser_state.msg_type), 2, 0);
crc = crc16_ccitt((uint8_t*)&(parser_state.sender_id), 2, crc);
crc = crc16_ccitt(&(parser_state.msg_len), 1, crc);
crc = crc16_ccitt(parser_state.msg_buff, parser_state.msg_len, crc);
if (parser_state.crc == crc) {
_sbp_process_message();
} else {
Debug("CRC Error Occurred!");
crc_error_counter += 1;
}
parser_state.state = sbp_parser_state_t::WAITING;
}
break;
default:
parser_state.state = sbp_parser_state_t::WAITING;
break;
}
}
}
//INVARIANT: A fully received message with correct CRC is currently in parser_state
void
AP_GPS_SBP::_sbp_process_message() {
switch(parser_state.msg_type) {
case SBP_HEARTBEAT_MSGTYPE:
last_heatbeat_received_ms = AP_HAL::millis();
break;
case SBP_GPS_TIME_MSGTYPE:
memcpy(&last_gps_time, parser_state.msg_buff, sizeof(last_gps_time));
break;
case SBP_VEL_NED_MSGTYPE:
memcpy(&last_vel_ned, parser_state.msg_buff, sizeof(last_vel_ned));
break;
case SBP_POS_LLH_MSGTYPE: {
struct sbp_pos_llh_t *pos_llh = (struct sbp_pos_llh_t*)parser_state.msg_buff;
// Check if this is a single point or RTK solution
// flags = 0 -> single point
if (pos_llh->flags == 0) {
last_pos_llh_spp = *pos_llh;
} else if (pos_llh->flags == 1 || pos_llh->flags == 2) {
last_pos_llh_rtk = *pos_llh;
}
break;
}
case SBP_DOPS_MSGTYPE:
memcpy(&last_dops, parser_state.msg_buff, sizeof(last_dops));
break;
case SBP_TRACKING_STATE_MSGTYPE:
//INTENTIONALLY BLANK
//Currenly unhandled, but logged after switch statement.
break;
case SBP_IAR_STATE_MSGTYPE: {
sbp_iar_state_t *iar = (struct sbp_iar_state_t*)parser_state.msg_buff;
last_iar_num_hypotheses = iar->num_hypotheses;
break;
}
default:
// log anyway if it's an unsupported message.
// The log mask will be used to adjust or suppress logging
break;
}
logging_log_raw_sbp(parser_state.msg_type, parser_state.sender_id, parser_state.msg_len, parser_state.msg_buff);
}
bool
AP_GPS_SBP::_attempt_state_update()
{
// If we currently have heartbeats
// - NO FIX
//
// If we have a full update available, save it
//
uint32_t now = AP_HAL::millis();
bool ret = false;
if (now - last_heatbeat_received_ms > SBP_TIMEOUT_HEATBEAT) {
state.status = AP_GPS::NO_GPS;
Debug("No Heartbeats from Piksi! Driver Ready to Die!");
ret = false;
} else if (last_pos_llh_rtk.tow == last_vel_ned.tow
&& abs((int32_t) (last_gps_time.tow - last_vel_ned.tow)) < 10000
&& abs((int32_t) (last_dops.tow - last_vel_ned.tow)) < 60000
&& last_vel_ned.tow > last_full_update_tow) {
// Use the RTK position
sbp_pos_llh_t *pos_llh = &last_pos_llh_rtk;
// Update time state
state.time_week = last_gps_time.wn;
state.time_week_ms = last_vel_ned.tow;
state.hdop = last_dops.hdop;
// Update velocity state
state.velocity[0] = (float)(last_vel_ned.n / 1000.0);
state.velocity[1] = (float)(last_vel_ned.e / 1000.0);
state.velocity[2] = (float)(last_vel_ned.d / 1000.0);
float ground_vector_sq = state.velocity[0]*state.velocity[0] + state.velocity[1]*state.velocity[1];
state.ground_speed = safe_sqrt(ground_vector_sq);
state.ground_course_cd = wrap_360_cd((int32_t) 100*ToDeg(atan2f(state.velocity[1], state.velocity[0])));
// Update position state
state.location.lat = (int32_t) (pos_llh->lat*1e7);
state.location.lng = (int32_t) (pos_llh->lon*1e7);
state.location.alt = (int32_t) (pos_llh->height*1e2);
state.num_sats = pos_llh->n_sats;
if (pos_llh->flags == 0)
state.status = AP_GPS::GPS_OK_FIX_3D;
else if (pos_llh->flags == 2)
state.status = AP_GPS::GPS_OK_FIX_3D_DGPS;
else if (pos_llh->flags == 1)
state.status = AP_GPS::GPS_OK_FIX_3D_RTK;
last_full_update_tow = last_vel_ned.tow;
last_full_update_cpu_ms = now;
logging_log_full_update();
ret = true;
} else if (now - last_full_update_cpu_ms > SBP_TIMEOUT_PVT) {
//INVARIANT: If we currently have a fix, ONLY return true after a full update.
state.status = AP_GPS::NO_FIX;
ret = true;
} else {
//No timeouts yet, no data yet, nothing has happened.
ret = false;
}
return ret;
}
bool
AP_GPS_SBP::_detect(struct SBP_detect_state &state, uint8_t data)
{
// This switch reads one character at a time, if we find something that
// looks like our preamble we'll try to read the full message length,
// calculating the CRC. If the CRC matches, we have an SBP GPS!
switch(state.state) {
case SBP_detect_state::WAITING:
if (data == SBP_PREAMBLE) {
state.n_read = 0;
state.crc_so_far = 0;
state.state = SBP_detect_state::GET_TYPE;
}
break;
case SBP_detect_state::GET_TYPE:
state.crc_so_far = crc16_ccitt(&data, 1, state.crc_so_far);
state.n_read += 1;
if (state.n_read >= 2) {
state.n_read = 0;
state.state = SBP_detect_state::GET_SENDER;
}
break;
case SBP_detect_state::GET_SENDER:
state.crc_so_far = crc16_ccitt(&data, 1, state.crc_so_far);
state.n_read += 1;
if (state.n_read >= 2) {
state.n_read = 0;
state.state = SBP_detect_state::GET_LEN;
}
break;
case SBP_detect_state::GET_LEN:
state.crc_so_far = crc16_ccitt(&data, 1, state.crc_so_far);
state.msg_len = data;
state.n_read = 0;
state.state = SBP_detect_state::GET_MSG;
break;
case SBP_detect_state::GET_MSG:
state.crc_so_far = crc16_ccitt(&data, 1, state.crc_so_far);
state.n_read += 1;
if (state.n_read >= state.msg_len) {
state.n_read = 0;
state.state = SBP_detect_state::GET_CRC;
}
break;
case SBP_detect_state::GET_CRC:
*((uint8_t*)&(state.crc) + state.n_read) = data;
state.n_read += 1;
if (state.n_read >= 2) {
state.state = SBP_detect_state::WAITING;
return state.crc == state.crc_so_far;
}
break;
default:
state.state = SBP_detect_state::WAITING;
break;
}
return false;
}
#if SBP_HW_LOGGING
void
AP_GPS_SBP::logging_log_full_update()
{
if (gps._DataFlash == NULL || !gps._DataFlash->logging_started()) {
return;
}
struct log_SbpHealth pkt = {
LOG_PACKET_HEADER_INIT(LOG_MSG_SBPHEALTH),
time_us : AP_HAL::micros64(),
crc_error_counter : crc_error_counter,
last_injected_data_ms : last_injected_data_ms,
last_iar_num_hypotheses : last_iar_num_hypotheses,
};
gps._DataFlash->WriteBlock(&pkt, sizeof(pkt));
};
void
AP_GPS_SBP::logging_log_raw_sbp(uint16_t msg_type,
uint16_t sender_id,
uint8_t msg_len,
uint8_t *msg_buff) {
if (gps._DataFlash == NULL || !gps._DataFlash->logging_started()) {
return;
}
//MASK OUT MESSAGES WE DON'T WANT TO LOG
if (( ((uint16_t) gps._sbp_logmask) & msg_type) == 0) {
return;
}
uint64_t time_us = AP_HAL::micros64();
struct log_SbpRAW1 pkt = {
LOG_PACKET_HEADER_INIT(LOG_MSG_SBPRAW1),
time_us : time_us,
msg_type : msg_type,
sender_id : sender_id,
msg_len : msg_len,
};
memcpy(pkt.data1, msg_buff, MIN(msg_len,64));
gps._DataFlash->WriteBlock(&pkt, sizeof(pkt));
if (msg_len > 64) {
struct log_SbpRAW2 pkt2 = {
LOG_PACKET_HEADER_INIT(LOG_MSG_SBPRAW2),
time_us : time_us,
msg_type : msg_type,
};
memcpy(pkt2.data2, &msg_buff[64], msg_len - 64);
gps._DataFlash->WriteBlock(&pkt2, sizeof(pkt2));
}
};
#endif // SBP_HW_LOGGING