> Yes, I implemented both commands, I can share the code with you.

It would be great. Just send these patches here using git
format-patch / send-email. I'll have a look.

> My problem is that Gnuradio (distro version) is built against an
> incompatible ABI version of libuhd, so I have to jump through
> major hoops just to get both osmo-trx and gnuradio working.
> So currently all my tests are using osmo-trx only.

Ah, just build it yourself. It would be much better.
Distro versions are often pretty dated :(
Excluding Arch Linux and similar ;)

> Yes, the SCH burst has a correct frame number.
> But the BCCH and CCCH bursts fail to be decoded. CRC fails in
> libosmocore/coding/gsm0503_coding.c

Regarding to the 'bits conversation' you mentioned in the first
mail, it's done the same way as in OsmoBTS. It should work as is.
Probably SCH bursts are not actually forwarded from OsmoTRX. Or
being forwarded in a wrong way.

> Is your gr-gsm fake-trx able to decode correctly BCCH and CCCH?

Sure. I am even able to make a voice call.