[linux-dvb] qam256 problem with Technotrend C2300 DVB-C card

Andrew de Quincey adq_dvb at lidskialf.net
Fri Nov 17 12:15:19 CET 2006

On Sunday 08 October 2006 08:43, e9hack wrote:
> Hi,
> I've problems with the TT-C2300 DVB-C card and qam256 modulated channels.
> After switching to a qam256 channel, the card needs between 0.5 and 1 hour
> to get the lock. Possible it is a problem of the reduced i2c bus speed. If
> the stv0297 is accessed with a higher i2c bus speed, the card gets the lock
> within a few seconds like qam64. I've attach a patch, which does reduce the
> i2c bus speed for the tuner only. I've measured the time between 'after
> tuning' and 'start waiting for the agc lock' in stv0297_set_frontend().
> Without the patch it needs 470ms and with the patch 60ms. This is a little
> bit strange, because the factor of the speed changing is two. Possible,
> there is a bug in the spec of the saa7146.

Looks sensible to me; no point slowing the demod access just for the tuner. 
Will commit once you send me a signed off by line for it...

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