MC7710: switch from MBIM mode


#1

MC7710 module (QMI, PID = 68A2) has been occasionally switched to MBIM-only mode (USB composition #9).
How do I get it back to original (#6) composition? No ports are available to send command to anymore…


#2

Please contact your distributor or FAE for way to recover it.

Try to use UDUSBCOMP mode 14 if you want to support Win 8 with the flexibility to use QMI mode on non Win 8 platform.

Thx


#3
14 - Config1: comp6    Config2: comp9             SUPPORTED

How could I switch between Config1 and Config2?


#4

Module configured with mode 14 will switch between config1 and config2 depends on OS connected.

Please contact your distributor or FAE for info.

Thx


#5

If you’re using Linux, you can switch configurations by simply writing to
/sys/bus/usb/devices//bConfigurationValue

E.g

echo 1 >/sys/bus/usb/devices/5-4/bConfigurationValue

You should only do this immediately after booting the module, due to a couple of bugs in the current firmware: The network function switches based on input detection. So it will stay MBIM after switching if you ever spoke MBIM to it, despite the USB descriptors switching to QMI. And even if you avoid sending any MBIM command, I’ve observed the QMI function spit out an endless stream of zero byte packets if the switch happened after loading a MBIM driver. The rate is high enough to possibly kill the host.