[linux-dvb] TT C1500 "new version" problems

Heikki Lindholm holindho at cs.helsinki.fi
Sat Jan 26 08:42:46 CET 2008


e9hack kirjoitti:
> Hi,
> 
> the WinXP driver for the TT C1500 initialize the pll in a different manner like linux:
> 
> Divider: 1ae2 -> 394MHz
> 16.10.07 19:06:16.543: S c2(W) A 1a A e2 A c8 A 62 A 80 A P
> 16.10.07 19:06:16.602: S c2(W) A 1a A e2 A c8 A c2 A 80 A P
> 
> 16.10.07 19:06:16.916: S c2(W) A 1a A e2 A c8 A 6a A 80 A P
> 16.10.07 19:06:16.982: S c2(W) A 1a A e2 A c8 A ca A 80 A P
> 
> 16.10.07 19:06:17.340: S c2(W) A 1a A e2 A c8 A 62 A 80 A P
> 16.10.07 19:06:17.408: S c2(W) A 1a A e2 A c8 A c2 A 80 A P
> 
> 16.10.07 19:06:18.714: S c2(W) A 1a A e2 A c8 A 6a A 80 A P
> 16.10.07 19:06:18.781: S c2(W) A 1a A e2 A c8 A ca A 80 A P
> 
> Divider: 1e62 -> 450MHz
> 16.10.07 19:06:21.422: S c2(W) A 1e A 62 A c8 A 6c A 80 A P
> 16.10.07 19:06:21.479: S c2(W) A 1e A 62 A c8 A 6c A 80 A P
> 
> 16.10.07 19:06:22.015: S c2(W) A 1e A 62 A c3 A 44 A P <- Überlauf?
> 16.10.07 19:06:22.015: S c2(W) A 1e A 62 A c8 A 64 A 80 A P
> 
> After 60ms, the charge pump value is changed (0x62->0xc2). This occurs on 394MHz but not 
> on 450MHz. The band width bit is inverted on every tuning attempt (0x62->0x6a->0x62).

Maybe they monitor the signal quality from a thread and increase charge 
pump only if necessary, always(?) starting with (6>>1). After locking, 
does the bandwidth bit stay at the same value for a given channel on all 
attempts, i.e., it's not sometimes zero sometimes one.

I tried the bandwidth bit inversion with Linux, but I see no difference 
in behaviour. Tuner locks just as well with both settings and the signal 
qualities are essentially the same.

Can you also see what happens at the demodulator chip on XP? Btw., I 
take it the stv0297 specs aren't available anywhere(?)

-- Heikki Lindholm




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