By any chance, you got a dismantled
A720 (or similar with the same 8MB sensor) lying around?
The reason I'm asking is this: It would be nice to control CCD voltages from the software, most of all the preamp Vdd (just to be able to turn it off, of course!) While it is clearly impossible in general (lack of hardware capabilities), there might exist limited software access for some sensors.
The firmware of my
Ixus950 (and I believe all other cameras with the same sensor --
A720, S5,
Ixus80 to name a few) contains an interesting piece of code VsubCont.c, called from ImageSensorTask. The name immediately raises suspicion, as it reminds the mnemonics of Substrate Voltage Control in some CCD chips. The function (located at FF9B9C3C in my case) writes to three hardware ports (CCD voltage control??), 0xC022009C, 0xC0F18010, and 0xC0220090. Calling it with allowed parameters 1,2,4,8 doesn't produce anything spectacular -- just changing the live image brightness a bit. But does it actually change CCD voltages, and if so, which ones? The best way to find out would be to hook up a voltmeter to the sensor pins while writing to these ports -- but this requires opening up the cam, which I don't like. I thought you might have already taken one apart.
