Mavlink library_v2

[marvin199]

I am trying to use a Pixhawk 4 to send current information from the ESC to the Arduino Uno. I am using Understanding the Arduino Mavlink library | Lo.C.A.R.B. as a reference. By including mavlink.h at the top of the script, I have access to library_v1 under mavlink. Unfortunately, I want to use a header file only in library_v2 and I am having problems running this library.

In Mavlink.io (Messages (common) · MAVLink Developer Guide) I have found the header file I am looking for (ESC_STATUS (#291)) " mavlink_msg_esc_status.h, however, I am getting error messages including it and trying to use its variables ("Error compiling for board Arduino Uno.") I am able to use header files imported from mavlink.h such as mavlink_msg_gps_raw_int.h with no problems.

I would appreciate any help or advice getting this running. My code is below.

#include "mavlink.h"
#include "mavlink_msg_esc_status.h"
#include <SoftwareSerial.h>

#define RXpin 2
#define TXpin 3
SoftwareSerial SerialMAV(RXpin, TXpin); // sets up serial communication on pins 3 and 2

void setup() {
  SerialMAV.begin(9600); //RXTX from Pixhawk (Port 19,18 Arduino Mega)
  Serial.begin(9600); //Main serial port for console output

request_datastream();

}

void loop() {

MavLink_receive();

}

//function called by arduino to read any MAVlink messages sent by serial communication from flight controller to arduino
void MavLink_receive()
  { 
  mavlink_message_t msg;
  mavlink_status_t status;

  while(SerialMAV.available())
  {
    uint8_t c= SerialMAV.read();

    //Get new message
    if(mavlink_parse_char(MAVLINK_COMM_0, c, &msg, &status))
    {

    //Handle new message from autopilot
      switch(msg.msgid)
      {
//
    //    case MAVLINK_MSG_ID_GPS_RAW_INT:
//      {
//        mavlink_gps_raw_int_t packet;
//        mavlink_msg_gps_raw_int_decode(&msg, &packet);
//        
//        Serial.print("\nGPS Fix: ");Serial.println(packet.fix_type);
//        Serial.print("GPS Latitude: ");Serial.println(packet.lat);
//        Serial.print("GPS Longitude: ");Serial.println(packet.lon);
//        Serial.print("GPS Speed: ");Serial.println(packet.vel);
//        Serial.print("Sats Visible: ");Serial.println(packet.satellites_visible);

         case MAVLINK_MSG_ID_ESC_STATUS:
      {
        __mavlink_esc_status_t packet;
        mavlink_msg_esc_status_decode(&msg, &packet);

        for (int i=0; i<=4; i++){
          Serial.print("\nCurrent Draw: ");
          Serial.print(i);
          Serial.println(packet.current[i]);
        }
          
//         case MAVLINK_MSG_ID_SERVO_OUTPUT_RAW:
//        {
//          __mavlink_servo_output_raw_t packet;
//          mavlink_msg_servo_output_raw_decode(&msg, &packet);
//
//          Serial.print("Servo Output: ");
//          Serial.print(packet.servo1_raw);
        }
      break;

      }
    }
  }
}


void request_datastream() {
//Request Data from Pixhawk
  uint8_t _system_id = 255; // id of computer which is sending the command (ground control software has id of 255)
  uint8_t _component_id = 2; // seems like it can be any # except the number of what Pixhawk sys_id is
  uint8_t _target_system = 1; // Id # of Pixhawk (should be 1)
  uint8_t _target_component = 0; // Target component, 0 = all (seems to work with 0 or 1
  uint8_t _req_stream_id = MAV_DATA_STREAM_ALL;
  uint16_t _req_message_rate = 0x01; //number of times per second to request the data in hex
  uint8_t _start_stop = 1; //1 = start, 0 = stop

// STREAMS that can be requested
  /*
   * Definitions are in common.h: enum MAV_DATA_STREAM and more importantly at:
     https://mavlink.io/en/messages/common.html#MAV_DATA_STREAM
   *   
   * MAV_DATA_STREAM_ALL=0, // Enable all data streams
   * MAV_DATA_STREAM_RAW_SENSORS=1, /* Enable IMU_RAW, GPS_RAW, GPS_STATUS packets.
   * MAV_DATA_STREAM_EXTENDED_STATUS=2, /* Enable GPS_STATUS, CONTROL_STATUS, AUX_STATUS
   * MAV_DATA_STREAM_RC_CHANNELS=3, /* Enable RC_CHANNELS_SCALED, RC_CHANNELS_RAW, SERVO_OUTPUT_RAW
   * MAV_DATA_STREAM_RAW_CONTROLLER=4, /* Enable ATTITUDE_CONTROLLER_OUTPUT, POSITION_CONTROLLER_OUTPUT, NAV_CONTROLLER_OUTPUT.
   * MAV_DATA_STREAM_POSITION=6, /* Enable LOCAL_POSITION, GLOBAL_POSITION/GLOBAL_POSITION_INT messages.
   * MAV_DATA_STREAM_EXTRA1=10, /* Dependent on the autopilot
   * MAV_DATA_STREAM_EXTRA2=11, /* Dependent on the autopilot
   * MAV_DATA_STREAM_EXTRA3=12, /* Dependent on the autopilot
   * MAV_DATA_STREAM_ENUM_END=13,
   * 
   * Data in PixHawk available in:
   *  - Battery, amperage and voltage (SYS_STATUS) in MAV_DATA_STREAM_EXTENDED_STATUS
   *  - Gyro info (IMU_SCALED) in MAV_DATA_STREAM_EXTRA1
   */

  // Initialize the required buffers
  mavlink_message_t msg;
  uint8_t buf[MAVLINK_MAX_PACKET_LEN];

  // Pack the message
  mavlink_msg_request_data_stream_pack(_system_id, _component_id, &msg, _target_system, _target_component, _req_stream_id, _req_message_rate, _start_stop);
  uint16_t len = mavlink_msg_to_send_buffer(buf, &msg);  // Send the message (.write sends as bytes)

  SerialMAV.write(buf, len); //Write data to serial port
}