I'm working with SIM800L for remote-sensing communication via GPRS. The problem is, everytime the module is running initialization function (SIM800.begin(), different for every SIM800L library), it failed.
I have check whether the module is broken or not, by connecting RX & TX pin of the SIM800L module to the TX & RX pin of FTDI module, and send AT command from PC serial monitor. The module seems not broken, as it still can reply the AT commands.
The program is failed to attempt to open comm with ATs, and keep looping on the AT sending. How can i fix this issue? Thank you.
[Extra: i use 2-cell 7.4V Li-Po battey, and it is regulated with XL4015 module to 4V, as the module work on 3.4-4.4V. Could this be the cause of the problem (too weak power supply)?]