Hello,
I've recently started using the GSM shield to enable me to upload sensor readings to a webserver using HTTP post. I have got the basics of the project working but the issue is that the GSM shield only seems to work intermittently.
The standard sketches that are provided do not all work, the GSMNetworksScanner returns the IMEI as 0 and no networks are found, sending an SMS works sometimes and sometimes not. It seems random when I hit the reset button if it is going to work or not.
When it works it's perfect it's just the intermittent issues that are really frustrating. I've tried multiple SIM cards but the issue remains.
Any advice would be appreciated as I don't wan't to give up on this project.
Regards,
David
I'd be guessing the power could be a problem - or your code.
Generally I haven't seen any reliability issues once I figured out what I was doing wrong!
What modem / chipset are you using? There are iny variations between some modems.
Remember the 2G bands will be closing down over the next year or so.
I'm using the Quectel M10 chipset and just running the standard sketches supplied in the IDE. As an example the send SMS sketch will maybe work 2 out of 5 times of trying.
I may investigate if it's possible to communicate with it without using the GSM library.
Definitely...
Simple serial comms, then you can see when it's falling over.
Or you can put some Serial.prints in to echo the sent and received strings.
Check your signal strength with the AT+CSQ command. Your signal may may be too weak.