PLS8-E AT^SQPORT command returns an error status but no actual error string | Thales IoT Developer Community

Hello,

I'm starting some development work on a PLS8-E development board for embedded Linux 3.18.14 (ARM). Presently I getting familiar with the AT command set. When the board is plugged in and powered on I see the following devices: /dev/ttyACM0, /dev/ttyACM1, /dev/ttyACM2, /dev/ttyACM3. I'm assuming that ttyACM0 is the 'modem' port and ttyACM1 is the 'application' port but what are ttyACM2 and ttyACM3 used for?

I'm using ttyACM1 to write AT commands and read the responses. It all seem fine as far as it goes.

When I send the AT^SQPORT? command I get the response

AT^sqport?

ERROR

but there is no actual error message as part of the response to the command. I was expecting a response something like "Application".

I tried

                AT+CMEE?

and get the response

                +CMEE: 2

so I should be getting verbose string values for error results.

Can anybody give and advice as to what I'm doing wrong?

Thanks