Linux DIAG port

1

Hello,

I am interested in the DIAG port. On my linux embedded system, I have an EM9293 in MBIM mode

(AT!USBCOMP? returns:

AT!USBCOMP?
Config Index: 1
Config Type: 4 (MBIM V2)
Interface bitmask: 00001009 (diag,modem,mbim)

)

I have also enabled DIAGENABLE with AT!CUSTOM=“DIAGENABLE”,1.

When the modem is turned on, The linux OS gives me 2 serial devices (/dev/ttyUSB0 and 1) and /dev/cdc-wdm0. I can send and receive AT commands via /dev/ttyUSB0. Nothing seems to happen on ttyUSB1.

Where can I see diagnostic messages?

What is the purpose of the second serial port?

Should I have more serial ports? I expected a new one to appear when I turned the diagenable on…

2

/dev/ttyUSB1 is the DM port for getting QXDM log for network analysis.

you can download the linux tool here:

To get the DM log, you can type the following as example:

owner@ubuntu:~/QMI/MBPL/MBPL_Tools_R26_ENG2.src/tools/dm-logger$ sudo ./bin/dm-loggerhostx86_64 -p /dev/ttyUSB1 -c filters/Default.cfg -o log_EM9291.qmdl