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All things pertaining to wireless and RF links
By jtsh
#25327
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.
By cabbage
#25478
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