Hi Guys,
I've been battling with my SIM 800L module for a couple of days now with no joy, I've been trying things and eliminating possible causes.
The specific type of module I have is this one: http://img.dxcdn.com/productimages/sku_406905_1.jpg
Currently I have it hooked up to an Arduino UNO using a LLC. The Arduino is powered via USB, and supplies the HV pin on the LLC with 5v from the 5v pin on the Arduino. The LV pin has 2.8v going into it from an LM2596 DC-DC converter and the SIM800L module its self gets 4.2v from another LM2596 DC-DC converter, both converters are powered from the same 10,000mah 12v battery.
I can confirm that I can make a connection with the module via the Arduino as when sending AT I get an OK back. I can also read the module information.
I am on the giffgaff network (more or less o2 here in the UK) and the SIM I have in the device is a nano sim (on the back there are a bunch of letters and numbers, 4G appears among them).
I am getting +CPIN: READY with the CPIN command but when I try AT+CGREG? I get +CGREG: 0,0 most of the time or occasionally +CGREG: 0,2 (which i think means searching?). Regardless I am never getting +CGREG: 0,1 which means its connected to the network.
I have no idea if the sim card I am using is in compatible with the module or if I have just damaged the module. Everything it wired up properly and I have measured the volts and amps and everything it getting the right amount of power.I have not tried another sim card in it yet from another net work, I still trying to understand why a 4G would cause problems, as I can pop it into my phone, select the 2g network only and it works fine, any help is much appreciated.
Thanks,
-Anton