Cellular Network Infrastructure » Radio Access Network » OsmoBTS

Fix is waiting for review in gerrit #691.

Note to self: FACCH should also trigger onset event followed by actual data.

Gerrit #691 has been merged to master but in dsp trace there are still missing onset frames - most likely due to some issue with libosmoabis which leads to marker bit not being propagated to callback function. Investigation is in progress.

Should be fixed by gerrit # 1030, 1031. Waiting for test confirmation.

The reason ONSET is not sent on talkspurt is broken metadata (markbit) from ortp:

The macros like rtp_get_markbit() are defined as follows:

#define rtp_get_markbit(mp)»····(((rtp_header_t*)((mp)->b_rptr))->markbit)

so they use mp->b_rptr as a pointer to the header of the RTP packet.

However, the current code, you first use something like
rtp_get_payload(mp, &mp->b_rptr);

Which usee b_rptr as an output value and actually advances it to the
start of the packet payload.

I strongly suggest that you use something like
uint8_t *payload;
int payload_size;
payload_size = rtp_get_payload(mp, &payload);

which will keep b_rptr pointing to the header and thus make the
above-mentioend macros still work.

With latest fix to libosmo-abis we're no getting marker bit and hence sending onset.