AirPrime MC7700 Firmware Downgrade?

I have a collection of MikroTik Routerboards that can use MC7700 air cards, but they only seem to work with a certain firmware revision. The cards I have were bought at different times, and some of them I’ve upgraded to the current firmware ( myself using the upgrade tool from Sierra, but right now I only have one that’s recognized in RouterOS. All the cards seem to be identical, except for the firmware revision, and they all work when I connect them to a Windows machine, so the hardware itself is working. The card that’s working is using firmware, the full firmware string is “SWI9200X_03.05.10.02AP R4684 CARMD-EN-10527 2012/02/25 11 58:38”. My question is, is there a way to downgrade to a specific revision? The tool from Sierra just seems to flash the newest revision, and I couldn’t find any archive of older revisions on Source.

Hi @RevenstarTelecom,
I am not sure if “SWI9200X_03.05.10.02AP R4684 CARMD-EN-10527 2012/02/25 11 58:38” is an official FW or not. But you should use the FWs posted on Sierra source following the link. They were verified by Sierra before delivering to the customer.

What problem are you getting on the module using FW? Please share the error messages or screenshots.

I find it unlikely that the firmware revision should affect detection in any OS, with the exception of those only supporting MBIM since that was a late addition to the MC77xx firmware.

But these modules can be configured for DirectIP or QMI (RMNET) operation. The setting is stored in NVRAM and is independent of the firmware revision. Changing the mode affects the USB device ID, and can therefore easily explain why a module isn’t recognized by an OS which only supports one of the modes. It won’t affect Windows (or Linux) since they support either,.

So check the device ID of your modules using lsusb on Linux, or device manager on WIndows. DirectIP is 68A3 and QMI is 68A2. Then check with Mikrotik which device IDs they support.

Sierra Wireless used to have a oneclick Windows tool to switch modes, but it’s probably easier to just use AT commands. Connect to the AT port. and check current settings and options:


You’ll notice that only a few of the USBCOMP settings are marked as SUPPORTED. These are the ones that are supported in the currecnt (DirectIP or QMI) mode. Switch modes, and the other set of USBCOMP settings witll become SUPPORTED.

Changing from DirectIP to QMI:


Changing from QMI to DirectIP:


Reset the module after any change.

Writing most of this from almost 10 year old memories, so you might want to double check against the AT commands manual…