Example Code for Arduino(UART)-High Precision Positioning

Hardware preparation

• DFR0216-2 DFRduino UNO R3 × 1
• 4G GNSS-RTK High Precision Positioning Kit x1

Software preparation

• Arduino IDE Download Arduino IDE
• Download and install the RTK Library
• How to install libraries?

UART Wiring Diagram

Note：To use the UART interface on Uno, please refer to the Getting Started section and first modify the baud rate to 57600.

Other Preparation Work

1. Apply for a CORS account from a domestic service provider (e.g., China's Continuously Operating Reference Station network).
2. Replace the placeholders in the code with your CORS account details:
   • USER_NAME: CORS account username
   • USER_PASSWORD: CORS account password
   • SERVER_ADDR: CORS server IP address
   • MOUNT_POINT: CORS service mount point
   • port: CORS server port number

Sample Code

 /*!
  * @file  getGnss4G.ino
  * @brief Get gnss simple data at 4G mode
  * @copyright Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
  * @license The MIT License (MIT)
  * @author ZhixinLiu([email protected])
  * @version V0.5.0
  * @date 2024-10-28
  * @url https://github.com/DFRobot/DFRobot_RTK_4G
  */

#include "DFRobot_RTK_4G.h"

//#define I2C_COMMUNICATION  //use I2C for communication, but use the serial port for communication if the line of codes were masked

#ifdef  I2C_COMMUNICATION
  DFRobot_RTK_4G_I2C rtk(&Wire ,DEVICE_ADDR);
#else
/* -----------------------------------------------------------------------------------------------------
 * |  Sensor  | Connect line | Leonardo/Mega2560/M0 |    UNO    | ESP8266 | ESP32 |  microbit  |   m0  |
 * |   VCC    |=============>|        VCC           |    VCC    |   VCC   |  VCC  |     X      |  vcc  |
 * |   GND    |=============>|        GND           |    GND    |   GND   |  GND  |     X      |  gnd  |
 * |   RX     |=============>|     Serial1 TX1      |     5     |   5/D6  |  D2   |     X      |  tx1  |
 * |   TX     |=============>|     Serial1 RX1      |     4     |   4/D7  |  D3   |     X      |  rx1  |
 * ----------------------------------------------------------------------------------------------------*/
/* Baud rate cannot be changed */
  #if defined(ARDUINO_AVR_UNO) || defined(ESP8266)
    SoftwareSerial mySerial(4, 5);
    DFRobot_RTK_4G_UART rtk(&mySerial, 57600);
  #elif defined(ESP32)
    DFRobot_RTK_4G_UART rtk(&Serial1, 115200 ,/*rx*/D2 ,/*tx*/D3);
  #else
    DFRobot_RTK_4G_UART rtk(&Serial1, 115200);
  #endif
#endif

#define  USER_NAME      "chwj068746"
#define  USER_PASSWORD  "16409678"
#define  SERVER_ADDR    "119.3.136.126"
#define  MOUNT_POINT    "RTCM33"
uint16_t port = 8002;
String   result = "";
void setup()
{
  Serial.begin(115200);
  while(!rtk.begin()){
    Serial.println("NO Deivces !");
    delay(1000);
  }
  Serial.println("Device connected !");
  rtk.setModule(eMoudle4g);
  while(rtk.getModule() != eMoudle4g){
    Serial.println("Module type is not 4G!  please wait!");
    delay(1000);
  }

  rtk.setUserName(USER_NAME, strlen(USER_NAME));
  rtk.setUserPassword(USER_PASSWORD, strlen(USER_PASSWORD));
  rtk.setServerAddr(SERVER_ADDR, strlen(SERVER_ADDR));
  rtk.setMountPoint(MOUNT_POINT, strlen(MOUNT_POINT));
  rtk.setPort(port);
  Serial.println("please wait 4g module init!");
  Serial.println("connecting network please wait !");
  result = rtk.connect();
  if((String)CONNECT_SUCCESS == result){
    Serial.println("connect success");
  }else{
    Serial.println(result);
  }
  
}

void loop()
{
  bool state = rtk.getDataFlush();
  if(state == true){
    sTim_t utc = rtk.getUTC();
    sTim_t date = rtk.getDate();
    sLonLat_t lat = rtk.getLat();
    sLonLat_t lon = rtk.getLon();
    double high = rtk.getAlt();
    uint8_t starUserd = rtk.getNumSatUsed();
    double hdop = rtk.getHdop();
    double sep = rtk.getSep();
    uint8_t mode = rtk.getQuality();
    uint16_t siteID = rtk.getSiteID();
    double diftime = rtk.getDifTime();

    Serial.println("");
    Serial.print(date.year);
    Serial.print("/");
    Serial.print(date.month);
    Serial.print("/");
    Serial.print(date.date);
    Serial.print("/");
    Serial.print(utc.hour);
    Serial.print(":");
    Serial.print(utc.minute);
    Serial.print(":");
    Serial.print(utc.second);
    Serial.println();
    Serial.println((char)lat.latDirection);
    Serial.println((char)lon.lonDirection);
    
    // Serial.print("lat DDMM.MMMMM = ");
    // Serial.println(lat.latitude, 5);
    // Serial.print(" lon DDDMM.MMMMM = ");
    // Serial.println(lon.lonitude, 5);
    Serial.print("lat degree = ");
    Serial.println(lat.latitudeDegree,6);
    Serial.print("lon degree = ");
    Serial.println(lon.lonitudeDegree,6);

    Serial.print("star userd = ");
    Serial.println(starUserd);
    Serial.print("alt high = ");
    Serial.println(high);
    Serial.print("sep  = ");
    Serial.println(sep);

    Serial.print("hdop = ");
    Serial.println(hdop);
    Serial.print("message mode  = ");
    Serial.println(mode);
    Serial.print("siteID = ");
    Serial.println(siteID);
    Serial.print("diftime = ");
    Serial.println(diftime);
    Serial.println(rtk.getGnssMessage(eGGA));
    Serial.println(rtk.getGnssMessage(eRMC));
    Serial.println(rtk.getGnssMessage(eGLL));
    Serial.println(rtk.getGnssMessage(eVTG));
  }
  if(!rtk.getConnectState()){
    Serial.println("restart connect .....");
    rtk.reConnect();
  }
  delay(800);
}

Result