optimize imu init error and examples name

components/ext_devs/ext_dev/include/maix_imu.hpp

@@ -172,7 +172,7 @@ public:
     /**
      * @brief Construct a new IMU object, will open IMU
      *
-     * @param driver driver name, only support "qmi8656"
+     * @param driver driver name, "default" means use onboard IMU according to board id, other values: ["qmi8656"]
      * @param i2c_bus i2c bus number. Automatically selects the on-board imu when -1 is passed in.
      * @param addr IMU i2c addr.
      * @param freq IMU freq
@@ -182,6 +182,7 @@ public:
      * @param gyro_scale gyro scale, see @imu::GyroScale
      * @param gyro_odr gyro output data rate, see @imu::GyroOdr
      * @param block block or non-block, defalut is true
+     * @throw if arg error or not find valid IMU, will throw err::Exception
      *
      * @maixpy maix.ext_dev.imu.IMU.__init__
      */

components/ext_devs/ext_dev/src/maix_imu.cpp

@@ -93,11 +93,23 @@ IMU::IMU(std::string driver, int i2c_bus, int addr, int freq, imu::Mode mode, im
     imu_param_t *param = (imu_param_t *)malloc(sizeof(imu_param_t));
     err::check_null_raise(param, "Failed to malloc param");
 
-    if(driver == "qmi8658")
+    bool found = false;
+
+    if(driver == "default")
+    {
+        if(sys::device_id() == "maixcam_pro")
+        {
+            param->type = driver_type::qmi8658;
+            found = true;
+        }
+    }
+    else if(driver == "qmi8658")
     {
         param->type = driver_type::qmi8658;
+        found = true;
     }
-    else
+
+    if (!found)
     {
         free(param);
         throw err::Exception(err::ERR_ARGS, "not support " + driver);

examples/ext_dev_imu_ahrs/main/src/main.cpp

@@ -151,21 +151,30 @@ int _main(int argc, char* argv[])
     std::vector<int> ret_btn_disp_pos = {0, disp.height() - 50, 100, 50};
     std::vector<int> dir_btn_disp_pos = {disp.width() / 2 - dir_font_size.width() / 2 - 10, disp.height() - 50, dir_font_size.width() + 20 , 50};
 
-    imu::IMU imu("qmi8658");
+    imu::IMU *imu = nullptr;
+    try
+    {
+        imu = new imu::IMU("default");
+    }
+    catch(...)
+    {
+        log::error("init IMU failed");
+        return 1;
+    }
     ahrs::MahonyAHRS ahrs(kp, ki);
     if(calibrate == 1)
     {
         log::info("now calibrate, please don't move device");
-        imu.calib_gyro(10000);
+        imu->calib_gyro(10000);
     }
     else
     {
-        imu.load_calib_gyro();
+        imu->load_calib_gyro();
     }
     char temp_char[64];
     double last_time = time::ticks_s();
     while (!app::need_exit()) {
-        auto data = imu.read_all(true, true); // use calibrate value and unit rad/s.
+        auto data = imu->read_all(true, true); // use calibrate value and unit rad/s.
         double t = time::ticks_s();
         float dt = t - last_time;
         auto angle = ahrs.get_angle(data.acc, data.gyro, data.mag, dt);
@@ -224,7 +233,7 @@ int _main(int argc, char* argv[])
             log::info("now calibrate, please don't move device");
             std::string msg = "Calibrating, don't move, keep 10s";
             show_msg(disp, msg);
-            imu.calib_gyro(10000);
+            imu->calib_gyro(10000);
             ahrs.reset();
             last_time = time::ticks_s();
         }
@@ -236,6 +245,7 @@ int _main(int argc, char* argv[])
         while(time::ticks_s() - last_time < 0.001)
             time::sleep_us(100);
     }
+    delete imu;
     return 0;
 }