--On den 24 juni 2003 12:49 +1000 John Dalgliesh <[EMAIL PROTECTED]> wrote:
I have no idea how I'd go about modifying the TDA10045H driver to use a different step size. As far as I can see, 167kHz is the resolution of the current calculation (1MHz/6) ... so I'd have to actually understand how those registers and the values written into them work... which I don't 8)
You would have to look in the tuner PLL circuit spec and see how to program it with another step size (if at all possible). The tuner PLL is on of the chips in the metal box. Its purpose is to make a signal that when mixed with the wanted input signal will make an IF signal of some constant and typically pretty low frequency, like 30 MHz or so, that is fed to the demodulator. In other words, it is programmed to generate a signal that is X Hz above or below the wanted signal, where X Hz is the center frequency that the demodulator wants its input signal to have.
You may be able to program it for another step size, which mean that you would also have to change 1/6MHz constant in the calculation accordingly.
Many of those PLLs seems to be very similar (in my very limited experience) and many of them can be programmed for two different step sizes. Note that the tuner module may use a different crystal frequency than the example in the PLL data sheet - you should be able to find out by the current tuning calculation.
I am not sure that you should have to, though, since I think the demodulator should be able to correct such a small offset. But I don't know, I know nothing about this demodulator.
Good luck!
/ragge
-- Info: To unsubscribe send a mail to [EMAIL PROTECTED] with "unsubscribe linux-dvb" as subject.
