Usage Example for Arduino-AT Command Communication-V2.0

In addition to controlling the SIM7600G-(H) module via the onboard USB virtual serial port on a PC, you can also use the Arduino IDE to debug the SIM7600G-(H) expansion board by sending AT commands through the Arduino serial port.

Hardware Preparation

• TEL0124 SIM7600G(-H) 4G(LTE) Shield x 1
• FIT0265 Micro USB Cable x 1
• DFR0216 DFRduino UNO R3 x 1
• Windows 11 PC x1
• SIM mobile card x1
• 7.4V external battery

Software Preparation

• Download and install the driver: Click to download driver

Operation Steps

1. Insert the SIM card into the expansion board and connect the SIM7600CE-T expansion board to Arduino UNO. Connect the external power supply.
2. Press the Boot button and wait for the SIM card to register on the network. The Net status indicator LED should enter fast flash mode (1 flash per second).
3. Depending on the control board type, use jumper caps to select D0/D1 or D7/D8 as the communication serial port.
4. In the following example, Arduino UNO is used. Download the code below to the UNO and use jumper caps to connect RX-D8/TX-D7.

Sample Code

#include <SoftwareSerial.h>
SoftwareSerial myserial(7, 8); // Define virtual serial port, Rx: 7, Tx: 8
void setup()
{
  myserial.begin(115200); // Initialize virtual serial port
  Serial.begin(115200); // Initialize Arduino default serial port
}

void loop()
{
  while (1) {
    while (myserial.available()) {
      Serial.write(myserial.read()); // If Serial receives data, output through mySerial
    }
    while (Serial.available()) {
      myserial.write(Serial.read()); // If mySerial receives data, output through Serial
    }
  }
}

After uploading the example code, open the built-in serial monitor in Arduino.

Send AT, and the serial port will return OK, indicating successful communication. Note (When using Arduino UNO for serial communication, since the module's default communication rate is 115200, the external crystal oscillation frequency can cause significant baud rate errors and garbled characters. It is recommended to use AT commands to modify the baud rate in the subsequent steps).

Send AT+IPREX=9600 to set the baud rate to 9600.

Then modify the communication rate of the UNO serial port and upload again.

#include <SoftwareSerial.h>
SoftwareSerial myserial(7, 8); // Define virtual serial port, Rx: 7, Tx: 8
void setup()
{
  myserial.begin(9600); // Initialize virtual serial port
  Serial.begin(9600); // Initialize Arduino default serial port
}

void loop()
{
  while (1) {
    while (myserial.available()) {
      Serial.write(myserial.read()); // If Serial receives data, output through mySerial
    }
    while (Serial.available()) {
      myserial.write(Serial.read()); // If mySerial receives data, output through Serial
    }
  }
}

Then, send AT and**AT+IPREX? **to the serial port using 9600 baud rate.The serial port will return OK and the current baud rate value, indicating that the communication rate modification was successful.