SIM800L not registering to network I am using SIM800L module. I am new to GSM modules. I have searched in many web sites about SIM800L, every where they mentioned baud rate 9600 for SoftwareSerial but it is not working at all in my case. So I started a trail and error method to match baud rate. Finally I found that its baud rate is 38400. With baud rate of 9600 for Arduino and 38400 I am able to communicate with SIM800L.

The problem is that I am unable to register to network. AT+COPS=? shows all available networks. Using AT+COPS="value" I am able to select network. But after that the SIM800L module still blinks every second.

In loop() I am continuously reading software serial and it's printing the following: 

RDY
+CFUN: 1
+CPIN: READY
Call Ready
SMS Ready
RDY
+CFUN: 1
+CPIN: READY
Call Ready
SMS Ready


The above data is continuously printing on console.
I am 90% sure it's a power issue. Not sure on what board/module you're using but the SIM800L/SIM900 needs a burst of current of 2&nbsp;A during 577&nbsp;µS (See the manual). 

Try using 4700&nbsp;µF and a 10&nbsp;µF capacitor in parallel with the module. Powering it with a proper power source instead of the Arduino wouldn't hurt too.