Sim800L cannot Init error

[PeteKnight]

@Deanr

SoftwareSerial SerialAT(2, 3); // RX, TX

@Deanr

SerialAT.begin(115200);

You should read this, especially the part about the maximum baud rates that you can successfully achieve with SoftwareSerial on an Uno…

Understanding hardware and software serial ports

I’m still seeing frequent posts, mostly from new members of the forum, who are confused about how to add WiFi or Bluetooth connectivity to devices like the Arduino Uno, Nano or Mega, or from people who are trying to use serial communication with some other type of peripheral. I thought I’d try to put together some guidance on how to do this properly. First things first though – if you’re using a device such as an Uno, Nano or Mega that doesn’t have built-in internet connectivity then you shoul…

You should also be careful about how you power the SIM800, as they can draw quite a lot of power in transmit mode.

Pete.