文章目录
- 资源
- 1. rcS启动
- 2. gps status内容
资源
px4_gps.md
标题： 闫刚 px4的gps驱动原理
1. rcS启动
固件版本： V1.8.0
gps start
2. gps status内容
INFO [gps] Main GPS
INFO [gps] protocol: UBX
INFO [gps] port: /dev/ttyS3, baudrate: 38400, status: OK
INFO [gps] sat info: disabled
vehicle_gps_position_s
timestamp: 134147543 (0.175065 seconds ago)
time_utc_usec: 0
lat: 102184774
lon: 1563467538
alt: 629117
alt_ellipsoid: 667558
s_variance_m_s: 67.698
c_variance_rad: 3.142
eph: 4294967.500
epv: 3750004.500
hdop: 99.990
vdop: 99.990
noise_per_ms: 109
jamming_indicator: 4
- gps helper定义
可以明显看出是1个多态处理
//父类
class GPSHelper
//ubox子类
class GPSDriverUBX : public GPSHelper
//mtK原理
class GPSDriverMTK : public GPSHelper
//
class GPSDriverAshtech : public GPSHelper
//父类指针，实现多态
GPSHelper *_helper; ///< instance of GPS parser
//创建子类对象
_helper = new GPSDriverUBX(_interface, &GPS::callback, this, &_report_gps_pos, _p_report_sat_info,
param_gps_ubx_dynmodel);
_helper = new GPSDriverMTK(&GPS::callback, this, &_report_gps_pos);
_helper = new GPSDriverAshtech(&GPS::callback, this, &_report_gps_pos, _p_report_sat_info);
- gps接收处理
gps接收数据驱动，很迷惑人，调用有深度。
while ((helper_ret = _helper->receive(TIMEOUT_5HZ)) > 0 && !should_exit()) {
-> while (true) {
bool ready_to_return = _configured ? (_got_posllh && _got_velned) : handled;
/* Wait for only UBX_PACKET_TIMEOUT if something already received. */
int ret = read(buf, sizeof(buf), ready_to_return ? UBX_PACKET_TIMEOUT : timeout);
-> int read(uint8_t *buf, int buf_length, int timeout) {
*((int *)buf) = timeout;
-> return _callback(GPSCallbackType::readDeviceData, buf, buf_length, _callback_user);
-> //poll -> read
int GPS::callback(GPSCallbackType type, void *data1, int data2, void *user)
case GPSCallbackType::readDeviceData: {
int num_read = gps->pollOrRead((uint8_t *)data1, data2, *((int *)data1));
-> int ret = poll(fds, sizeof(fds) / sizeof(fds[0]), math::min(max_timeout, timeout));
-> ret = ::read(_serial_fd, buf, buf_length);//gps
本文内容由网友自发贡献，版权归原作者所有，本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容，请联系:hwhale#tublm.com(使用前将#替换为@)
