I tried to use GSM900A mini module with Arduino UNO with Software Serial and Serial and also used Serial to USB converter also but still I did not get any response from it.
This is my video of Signal LED blink and connection. https://youtu.be/r5NGoSUxb8E
This Photo Shows communication pins with Arduino UNO.
I am from Sri Lanka and I used Sri Lankan Sim cards. GSM Module: SIM900A Mini v3.4 IMEI : 864161026832936.
Lastly I Tried
Your Video also but I did not get any call.
Please help me to sole this problem. How to test is from beginning?
Did you try this checklist?
The thing with SIM900/SIM800 is there can be multiple reasons that the AT commands are not working, I have listed down a few of them which i came across while working with SIM900 and SIM800 series modules, which can be helpful for debugging your...
Did you watch my Youtube Video. That Signal LED blinking method is different. What is your suggest?
Why AT command not working? I did not get any serial data.
As RaviPujar said, click on the link.
Then go there :
There is the list of regions restrictions. Sri Lanka is not in the list of compatibles regions.
On your video, at 1.40, we can see you power your module with the Arduino’s 5V.
If the Arduino’s power comes from a computer USB’s port, so the current is not enough.
Anyway, you must read documentation before choosing a module.