My SIM800L module continues to blink every second and AT command are not working. I did my connection right. Please I need help troubleshooting this.
Are you sure there is a 2G network still available at your location.
In many areas, these old networks are being phased out.
These commands should work even if you are not connected to a network.
Post your code.
Post how you have connected to the SIM800.
Yes I have 2G network in my location
So I connected the SIM800L to a 4.2V lithium battery, TX to D3 and RX to D2
Here is my code;
#include <SoftwareSerial.h>
#define rxPin 2
#define txPin 3
SoftwareSerial sim800L(rxPin,txPin);
void setup()
{
//Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
Serial.begin(115200);
//Begin serial communication with Arduino and SIM800L
sim800L.begin(9600);
Serial.println("Initializing...");
delay(1000);
}
void loop()
{
while(sim800L.available()){
Serial.println(sim800L.readString());
}
while(Serial.available()) {
sim800L.println(Serial.readString());
}
}
Shouldn't you have these connected the other way around so Rx->Tx, and Tx->Rx ?
also, try just read() rather than readString().
Alright I will try it out.
Thank you
Oh... and the other thing. You need to make sure you have a common ground (GND) between the Arduino and the SIM800.
Yes I made sure of that. What do you think about my baud rate. Both on the module and the arduino ?
For Software Serial you cannot go very fast... you can go a bit faster than 9600, but I wouldn't go higher than 19200.
You should probably make both the rates the same for this type of sketch, otherwise you potentially write faster than you can read.
What happens if you issue an "AT" command? Please show pics of your setup.
Also - based on this article...https://lastminuteengineers.com/sim800l-gsm-module-arduino-tutorial/
Looks like the SIM800L uses a 3.3v logic level. You may fry it if you connect directly to the Arduino (5v) - you need to use a voltage divider as in the article.
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