Sim800 a liitle help

[Timj22]

Hi I am using a D1 mini to control a SIM800. I am getting really confused about the need for newline \n and carriage return \r.

For starters when I enter AT with newline enabled it works fine and returns AT Ok. If I take off the new line and type AT I get no reply. If I take off the newline and then type AT\n I get no reply?

However the real problem is using the code.

In my code I have

Serial.println("AT+CMGF=1\r");
Serial.println("AT+CMGR=1,0\r");

Whatever combination I try the command appears on the serial monitor but the SIM800 just seems to ignore it. I am expecting it to print the first message stored as it does using the serial monitor and a TTL board.

I know I am missing something easy perhaps someone kind could help.

Thanks in advance

Tim

[J-M-L]

@Timj22

I know I am missing something easy perhaps someone kind could help.

I m not sure what you are missing, but WE are missing an exact description of your circuit and the code you use….

➜ do yourself a favour and please read How to get the best out of this forum and modify your post accordingly (including code tags and necessary documentation for your ask).

[red_car]

It would help if you posted your code.

Printing something to the Serial Monitor (Serial.print statements) is not the same as typing something into the Serial Monitor - they are sending information in opposite directions. You also can't type escape characters ("\") into the Serial Monitor and expect them to be interpreted.

[horace]

using an Arduino Mega with a SIM800L if I use statements such as

Serial1.println("AT+CGMM");
Serial1.println("AT+CGMR");
Serial1.println("AT+CGMI");

I get a response

AT+CGMM
SIMCOM_SIM800L
OK

AT+CGMR
Revision:1418B05SIM800L24
OK


AT+CGMI
SIMCOM_Ltd
OK