ardupilot/libraries/AP_HAL_AVR_SITL/sitl_gps.cpp

509 lines
12 KiB
C++

// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: t -*-
/*
SITL handling
This simulates a GPS on a serial port
Andrew Tridgell November 2011
*/
#include <AP_HAL.h>
#if CONFIG_HAL_BOARD == HAL_BOARD_AVR_SITL
#include <AP_HAL_AVR.h>
#include <AP_HAL_AVR_SITL.h>
#include "AP_HAL_AVR_SITL_Namespace.h"
#include "HAL_AVR_SITL_Class.h"
#include <AP_Math.h>
#include "../SITL/SITL.h"
#include "Scheduler.h"
#include "UARTDriver.h"
#include "../AP_GPS/AP_GPS.h"
#include "../AP_GPS/AP_GPS_UBLOX.h"
#include <sys/ioctl.h>
#include <unistd.h>
#include <time.h>
#include <sys/time.h>
using namespace AVR_SITL;
extern const AP_HAL::HAL& hal;
static uint8_t next_gps_index;
static uint8_t gps_delay;
SITL_State::gps_data SITL_State::_gps_data[MAX_GPS_DELAY];
// state of GPS emulation
static struct {
/* pipe emulating UBLOX GPS serial stream */
int gps_fd, client_fd;
uint32_t last_update; // milliseconds
} gps_state;
/*
hook for reading from the GPS pipe
*/
ssize_t SITL_State::gps_read(int fd, void *buf, size_t count)
{
#ifdef FIONREAD
// use FIONREAD to get exact value if possible
int num_ready;
while (ioctl(fd, FIONREAD, &num_ready) == 0 && num_ready > 256) {
// the pipe is filling up - drain it
uint8_t tmp[128];
if (read(fd, tmp, sizeof(tmp)) != sizeof(tmp)) {
break;
}
}
#endif
return read(fd, buf, count);
}
/*
setup GPS input pipe
*/
int SITL_State::gps_pipe(void)
{
int fd[2];
if (gps_state.client_fd != 0) {
return gps_state.client_fd;
}
pipe(fd);
gps_state.gps_fd = fd[1];
gps_state.client_fd = fd[0];
gps_state.last_update = _scheduler->millis();
AVR_SITL::SITLUARTDriver::_set_nonblocking(gps_state.gps_fd);
AVR_SITL::SITLUARTDriver::_set_nonblocking(fd[0]);
return gps_state.client_fd;
}
/*
write some bytes from the simulated GPS
*/
void SITL_State::_gps_write(uint8_t *p, uint16_t size)
{
while (size--) {
if (_sitl->gps_byteloss > 0.0) {
float r = ((((unsigned)random()) % 1000000)) / 1.0e4;
if (r < _sitl->gps_byteloss) {
// lose the byte
p++;
continue;
}
}
write(gps_state.gps_fd, p++, 1);
}
}
/*
send a UBLOX GPS message
*/
void SITL_State::_gps_send_ubx(uint8_t msgid, uint8_t *buf, uint16_t size)
{
const uint8_t PREAMBLE1 = 0xb5;
const uint8_t PREAMBLE2 = 0x62;
const uint8_t CLASS_NAV = 0x1;
uint8_t hdr[6], chk[2];
hdr[0] = PREAMBLE1;
hdr[1] = PREAMBLE2;
hdr[2] = CLASS_NAV;
hdr[3] = msgid;
hdr[4] = size & 0xFF;
hdr[5] = size >> 8;
chk[0] = chk[1] = hdr[2];
chk[1] += (chk[0] += hdr[3]);
chk[1] += (chk[0] += hdr[4]);
chk[1] += (chk[0] += hdr[5]);
for (uint8_t i=0; i<size; i++) {
chk[1] += (chk[0] += buf[i]);
}
_gps_write(hdr, sizeof(hdr));
_gps_write(buf, size);
_gps_write(chk, sizeof(chk));
}
/*
return GPS time of week in milliseconds
*/
static uint32_t millis_time_of_week(void)
{
struct tm tm;
struct timeval tv;
gettimeofday(&tv, NULL);
tm = *gmtime(&tv.tv_sec);
uint32_t tsec;
tsec =
tm.tm_wday * 24 * 3600 +
tm.tm_hour * 3600 +
tm.tm_min * 60 +
tm.tm_sec;
return tsec + (tv.tv_usec/1000);
}
/*
send a new set of GPS UBLOX packets
*/
void SITL_State::_update_gps_ubx(const struct gps_data *d)
{
#pragma pack(push,1)
struct ubx_nav_posllh {
uint32_t time; // GPS msToW
int32_t longitude;
int32_t latitude;
int32_t altitude_ellipsoid;
int32_t altitude_msl;
uint32_t horizontal_accuracy;
uint32_t vertical_accuracy;
} pos;
struct ubx_nav_status {
uint32_t time; // GPS msToW
uint8_t fix_type;
uint8_t fix_status;
uint8_t differential_status;
uint8_t res;
uint32_t time_to_first_fix;
uint32_t uptime; // milliseconds
} status;
struct ubx_nav_velned {
uint32_t time; // GPS msToW
int32_t ned_north;
int32_t ned_east;
int32_t ned_down;
uint32_t speed_3d;
uint32_t speed_2d;
int32_t heading_2d;
uint32_t speed_accuracy;
uint32_t heading_accuracy;
} velned;
struct ubx_nav_solution {
uint32_t time;
int32_t time_nsec;
int16_t week;
uint8_t fix_type;
uint8_t fix_status;
int32_t ecef_x;
int32_t ecef_y;
int32_t ecef_z;
uint32_t position_accuracy_3d;
int32_t ecef_x_velocity;
int32_t ecef_y_velocity;
int32_t ecef_z_velocity;
uint32_t speed_accuracy;
uint16_t position_DOP;
uint8_t res;
uint8_t satellites;
uint32_t res2;
} sol;
#pragma pack(pop)
const uint8_t MSG_POSLLH = 0x2;
const uint8_t MSG_STATUS = 0x3;
const uint8_t MSG_VELNED = 0x12;
const uint8_t MSG_SOL = 0x6;
pos.time = hal.scheduler->millis(); // FIX
pos.longitude = d->longitude * 1.0e7;
pos.latitude = d->latitude * 1.0e7;
pos.altitude_ellipsoid = d->altitude*1000.0;
pos.altitude_msl = d->altitude*1000.0;
pos.horizontal_accuracy = 5;
pos.vertical_accuracy = 10;
status.time = millis_time_of_week();
status.fix_type = d->have_lock?3:0;
status.fix_status = d->have_lock?1:0;
status.differential_status = 0;
status.res = 0;
status.time_to_first_fix = 0;
status.uptime = hal.scheduler->millis();
velned.time = status.time;
velned.ned_north = 100.0 * d->speedN;
velned.ned_east = 100.0 * d->speedE;
velned.ned_down = 100.0 * d->speedD;
velned.speed_2d = pythagorous2(d->speedN, d->speedE) * 100;
velned.speed_3d = pythagorous3(d->speedN, d->speedE, d->speedD) * 100;
velned.heading_2d = ToDeg(atan2f(d->speedE, d->speedN)) * 100000.0;
if (velned.heading_2d < 0.0) {
velned.heading_2d += 360.0 * 100000.0;
}
velned.speed_accuracy = 2;
velned.heading_accuracy = 4;
memset(&sol, 0, sizeof(sol));
sol.fix_type = d->have_lock?3:0;
sol.fix_status = 221;
sol.satellites = d->have_lock?10:3;
_gps_send_ubx(MSG_POSLLH, (uint8_t*)&pos, sizeof(pos));
_gps_send_ubx(MSG_STATUS, (uint8_t*)&status, sizeof(status));
_gps_send_ubx(MSG_VELNED, (uint8_t*)&velned, sizeof(velned));
_gps_send_ubx(MSG_SOL, (uint8_t*)&sol, sizeof(sol));
}
static void swap_uint32(uint32_t *v, uint8_t n)
{
while (n--) {
*v = htonl(*v);
v++;
}
}
/*
MTK type simple checksum
*/
static void mtk_checksum(const uint8_t *data, uint8_t n, uint8_t *ck_a, uint8_t *ck_b)
{
*ck_a = *ck_b = 0;
while (n--) {
*ck_a += *data++;
*ck_b += *ck_a;
}
}
/*
send a new GPS MTK packet
*/
void SITL_State::_update_gps_mtk(const struct gps_data *d)
{
#pragma pack(push,1)
struct mtk_msg {
uint8_t preamble1;
uint8_t preamble2;
uint8_t msg_class;
uint8_t msg_id;
int32_t latitude;
int32_t longitude;
int32_t altitude;
int32_t ground_speed;
int32_t ground_course;
uint8_t satellites;
uint8_t fix_type;
uint32_t utc_time;
uint8_t ck_a;
uint8_t ck_b;
} p;
#pragma pack(pop)
p.preamble1 = 0xb5;
p.preamble2 = 0x62;
p.msg_class = 1;
p.msg_id = 5;
p.latitude = d->latitude * 1.0e6;
p.longitude = d->longitude * 1.0e6;
p.altitude = d->altitude * 100;
p.ground_speed = pythagorous2(d->speedN, d->speedE) * 100;
p.ground_course = ToDeg(atan2f(d->speedE, d->speedN)) * 1000000.0;
if (p.ground_course < 0.0) {
p.ground_course += 360.0 * 1000000.0;
}
p.satellites = d->have_lock?10:3;
p.fix_type = d->have_lock?3:1;
// the spec is not very clear, but the time field seems to be
// seconds since the start of the day in UTC time, done in powers
// of 100. Quite bizarre.
struct tm tm;
struct timeval tv;
gettimeofday(&tv, NULL);
tm = *gmtime(&tv.tv_sec);
p.utc_time = tm.tm_sec + tm.tm_min*100 + tm.tm_hour*100*100;
swap_uint32((uint32_t *)&p.latitude, 5);
swap_uint32((uint32_t *)&p.utc_time, 1);
mtk_checksum(&p.msg_class, sizeof(p)-4, &p.ck_a, &p.ck_b);
_gps_write((uint8_t*)&p, sizeof(p));
}
/*
send a new GPS MTK 1.6 packet
*/
void SITL_State::_update_gps_mtk16(const struct gps_data *d)
{
#pragma pack(push,1)
struct mtk_msg {
uint8_t preamble1;
uint8_t preamble2;
uint8_t size;
int32_t latitude;
int32_t longitude;
int32_t altitude;
int32_t ground_speed;
int32_t ground_course;
uint8_t satellites;
uint8_t fix_type;
uint32_t utc_date;
uint32_t utc_time;
uint16_t hdop;
uint8_t ck_a;
uint8_t ck_b;
} p;
#pragma pack(pop)
p.preamble1 = 0xd0;
p.preamble2 = 0xdd;
p.size = sizeof(p) - 5;
p.latitude = d->latitude * 1.0e6;
p.longitude = d->longitude * 1.0e6;
p.altitude = d->altitude * 100;
p.ground_speed = pythagorous2(d->speedN, d->speedE) * 100;
p.ground_course = ToDeg(atan2f(d->speedE, d->speedN)) * 100.0;
if (p.ground_course < 0.0) {
p.ground_course += 360.0 * 100.0;
}
p.satellites = d->have_lock?10:3;
p.fix_type = d->have_lock?3:1;
// the spec is not very clear, but the time field seems to be
// hundreadths of a second since the start of the day in UTC time,
// done in powers of 100.
// The data is powers of 100 as well, but in days since 1/1/2000
struct tm tm;
struct timeval tv;
gettimeofday(&tv, NULL);
tm = *gmtime(&tv.tv_sec);
p.utc_date = (tm.tm_year-2000) + tm.tm_mon*100 + tm.tm_mday*100*100;
p.utc_time = tv.tv_usec/10000 + tm.tm_sec*100 + tm.tm_min*100*100 + tm.tm_hour*100*100*100;
p.hdop = 115;
mtk_checksum(&p.size, sizeof(p)-4, &p.ck_a, &p.ck_b);
_gps_write((uint8_t*)&p, sizeof(p));
}
/*
send a new GPS MTK 1.9 packet
*/
void SITL_State::_update_gps_mtk19(const struct gps_data *d)
{
#pragma pack(push,1)
struct mtk_msg {
uint8_t preamble1;
uint8_t preamble2;
uint8_t size;
int32_t latitude;
int32_t longitude;
int32_t altitude;
int32_t ground_speed;
int32_t ground_course;
uint8_t satellites;
uint8_t fix_type;
uint32_t utc_date;
uint32_t utc_time;
uint16_t hdop;
uint8_t ck_a;
uint8_t ck_b;
} p;
#pragma pack(pop)
p.preamble1 = 0xd1;
p.preamble2 = 0xdd;
p.size = sizeof(p) - 5;
p.latitude = d->latitude * 1.0e7;
p.longitude = d->longitude * 1.0e7;
p.altitude = d->altitude * 100;
p.ground_speed = pythagorous2(d->speedN, d->speedE) * 100;
p.ground_course = ToDeg(atan2f(d->speedE, d->speedN)) * 100.0;
if (p.ground_course < 0.0) {
p.ground_course += 360.0 * 100.0;
}
p.satellites = d->have_lock?10:3;
p.fix_type = d->have_lock?3:1;
// the spec is not very clear, but the time field seems to be
// hundreadths of a second since the start of the day in UTC time,
// done in powers of 100.
// The data is powers of 100 as well, but in days since 1/1/2000
struct tm tm;
struct timeval tv;
gettimeofday(&tv, NULL);
tm = *gmtime(&tv.tv_sec);
p.utc_date = (tm.tm_year-2000) + tm.tm_mon*100 + tm.tm_mday*100*100;
p.utc_time = tv.tv_usec/10000 + tm.tm_sec*100 + tm.tm_min*100*100 + tm.tm_hour*100*100*100;
p.hdop = 115;
mtk_checksum(&p.size, sizeof(p)-4, &p.ck_a, &p.ck_b);
_gps_write((uint8_t*)&p, sizeof(p));
}
/*
possibly send a new GPS packet
*/
void SITL_State::_update_gps(double latitude, double longitude, float altitude,
double speedN, double speedE, double speedD, bool have_lock)
{
struct gps_data d;
char c;
// 5Hz, to match the real config in APM
if (hal.scheduler->millis() - gps_state.last_update < 200) {
return;
}
// swallow any config bytes
if (gps_state.gps_fd != 0) {
read(gps_state.gps_fd, &c, 1);
}
gps_state.last_update = hal.scheduler->millis();
d.latitude = latitude;
d.longitude = longitude;
d.altitude = altitude;
d.speedN = speedN;
d.speedE = speedE;
d.speedD = speedD;
d.have_lock = have_lock;
// add in some GPS lag
_gps_data[next_gps_index++] = d;
if (next_gps_index >= gps_delay) {
next_gps_index = 0;
}
d = _gps_data[next_gps_index];
if (_sitl->gps_delay != gps_delay) {
// cope with updates to the delay control
gps_delay = _sitl->gps_delay;
for (uint8_t i=0; i<gps_delay; i++) {
_gps_data[i] = d;
}
}
if (gps_state.gps_fd == 0) {
return;
}
switch ((SITL::GPSType)_sitl->gps_type.get()) {
case SITL::GPS_TYPE_NONE:
// no GPS attached
break;
case SITL::GPS_TYPE_UBLOX:
_update_gps_ubx(&d);
break;
case SITL::GPS_TYPE_MTK:
_update_gps_mtk(&d);
break;
case SITL::GPS_TYPE_MTK16:
_update_gps_mtk16(&d);
break;
case SITL::GPS_TYPE_MTK19:
_update_gps_mtk19(&d);
break;
}
}
#endif