Unable to read and write on GSM Module

[vinothkumars]

Dear NXP,

I am working on SIMCOM GSM module. I am trying to execute AT command in this module. But, I am unable to access this module. 

I got the following reply when I try to read.

toradex_apalis6q:/ # cat /dev/ttyUSB3 &
[1] 1079
/system/bin/sh: cat: /dev/ttyUSB3: Try again

And also I check with all scenario (checking the user permission). But not workout.

Thanks & Regards,

VinothS

[vinothkumars · Accepted solution]

This the sim network problem and time zone problem. Finally this problem was when sim got network as well as by enabling the "automatic network prohibited time".

I closed this thread now.

Thanks,

VinothS

[b36401]

OK. Thanx for letting know.