Problem communicating with the GM862 Evaluation Kit - USB

Wireless & IoT
1

This is a bit long, but hopefully someone can tell me what I’m doing wrong. At this point I believe the module to be bad but any suggestions would be appreciated.

First, using my own serial port code in Linux, I was unable to receive a

response from the device. I opened the serial port, sent the “AT”

command and then the system blocked on a call to read() while

waiting for a response.

Next, via Minicom in Linux, I opened a connection to the device, but

failed to receive a response to the “AT” command (or any other

command).

Finally, I switched over to Windows and duplicated the procedure in

their guide that was on the website and I had the same result. After

sending the “AT” command – or any other command, I failed to receive a response.

I powered down the device between each attempt but was still unable to receive a response.

I tried all of the above both with a SIM card in the modem and without a

SIM card.

Any help would be appreciated.

2

When you plug the USB lead in, there should be a kernel message logged (use “dmesg” to see) - probably referring to ttyUSB0 but possibly a different number on the end. Then you need to open /dev/ttyUSB0 rather than ttyS0, for example.

You’ll need to change minicom to use that if you haven’t already.

Apologies if this all seems obvious - I thought I’d start from the beginning