PDTCH and PTCCH activation

Harald Welte laforge at gnumonks.org
Thu Jul 21 06:50:01 UTC 2016

Hi Max,

On Wed, Jul 20, 2016 at 06:50:24PM +0200, Max wrote:

> Notice that while PDTCH is activated for both UL and DL, the PTCCH is
> only activated for DL.
> As far as I've understood continuous TA procedure I've got to have PTCCH
> activated in both directions. The problem is that I have troubles
> locating the code which triggers the activation above.

from osmo-bts/src/osmo-bts-sysmo/oml.c:

static const struct sapi_dir pdtch_sapis[] = {
        { GsmL1_Sapi_Pdtch,»····GsmL1_Dir_TxDownlink },
        { GsmL1_Sapi_Pdtch,»····GsmL1_Dir_RxUplink },
        { GsmL1_Sapi_Ptcch,»····GsmL1_Dir_TxDownlink },
        { GsmL1_Sapi_Prach,»····GsmL1_Dir_RxUplink },
#if 0
        { GsmL1_Sapi_Ptcch,»····GsmL1_Dir_RxUplink },
        { GsmL1_Sapi_Pacch,»····GsmL1_Dir_TxDownlink },

I don't know exactly why it is commented out, probably because itw as
simply not used at the time?

- Harald Welte <laforge at gnumonks.org>           http://laforge.gnumonks.org/
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