My purpose was to send SMS using GSM SIM800L coreboard and Arduino UNO. Here is the code
#include <SoftwareSerial.h>
//Create a software serial object to communicate with SIM800L
SoftwareSerial mySerial(3, 2); //SIM800L Tx & Rx is connected to Arduino #3 & #2
void setup()
{
//Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
Serial.begin(115200);
//Begin serial communication with Arduino and SIM800L
mySerial.begin(115200);
Serial.println("Initializing...");
delay(1000);
mySerial.println("AT"); //Once the handshake test is successful, it will back to OK
updateSerial();
mySerial.println("AT+CMGF=1"); // Configuring TEXT mode
updateSerial();
mySerial.println("AT+CMGS=\"+ZZxxxxxxxxx\"");//change ZZ with country code and xxxxxxxxxxx with phone number to sms
updateSerial();
mySerial.print("TEST"); //text content
updateSerial();
mySerial.write(26);
}
void loop()
{
}
void updateSerial()
{
delay(500);
while (Serial.available())
{
mySerial.write(Serial.read());//Forward what Serial received to Software Serial Port
}
while(mySerial.available())
{
Serial.write(mySerial.read());//Forward what Software Serial received to Serial Port
}
}
And here is the serial monitor output
22:31:19.430 -> Initializing...
However, when I run the code, I get the text message to my mobile phone, but I can't see any AT commands in the serial monitor. It only outputs "Initializing..." . All the connections and baud rates are okay, checked a thousand times. Has connected 2A, 4.4v power supply to the GSM coreboard and shorten the wires, and sho No bad soldering joints. GSM module red led flash per 3 seconds. And again, I'm getting the text message to my phone. So that means the problem is with the Arduino serial monitor or code, not in the hardware. I need to see AT commands because I need to put more commands through the serial monitor, I tried typing and click send, But it's not showing anything. Any assistance you can provide would be greatly appreciated.
