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From: N_Cook on 25 Jun 2010 07:31
IanM <look.in.my.sig(a)totally.invalid> wrote in message
news:i022u4$2ree$1(a)energise.enta.net...
> N_Cook wrote:
> > From this odd named file
> > http://www.sh2a.com/Microsoft%20Word%20-%202A-cmos.pdf
> > and pins 1,2,3,4, 7 tied to Vss and p8 Vdd , then the 8 pinner marked
> > U274
> > 16B-1
> > probably an EEPROM but why ? NTSC/PAL selection would surely be just
taking
> > some pin high or low on the 48 pinner. Contrast and brightness carried
i2c
> > to the front end? will check later today
> >
> >
> >
> That PDF is for a USB camera which would need VID and PID info from
> somewhere, hence the EEPROM. Your one's VIMICRO VC0703 chip is
> configurable for a lot more than just PAL/NTSC. I would expect the OSD
> feature alone to need an EEPROM to store the text and the rest of the
> config might as well be kept in the same chip.
>
> --
> Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
> ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
> [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL:


there is only 4 wires between this camera pcb , down the 1m long spiral
trunking to the monitor etc, 0,3.3V, illumination LED supply (variable), and
CVBS signal out.


From: N_Cook on 28 Jun 2010 04:49
Repaired another of thse endoscope things, just mechanical damage to the
metal barrel surrounded "S video" connectors used as small polarised 4 way
connections. Sticking a 20D/ 50 mm focal length lens over the lens cover
means you can focus down to a conventional 16 pin DIL package to read
script. Image is then linear x2 so fills the height of the LCD screen.

If you were to cut away the waterproof lens cover and picked at the weak
glue around the LEDs and lens carrier you could unscrew it , web cam
fashion, to focus closer.
Anyway given up on this one , come to conclusion half the vimicro is kaput.
Annoyingly about 40 MHz clock and 9 output lines from the CCD work with
plenty of signal variation to content of view variation. But CVBS output is
corrupt , absolutely no image content. There are 3 sync pulses and 2 colour
bursts per line interval. Tried removing EEPROM as no clock burst , just
apparently matching L to H with 2 or 3 negative pulses only, then staying
high, on (presumably) SDA and SCK pins. Removed EEPROM and same signal on
vimicro pins , but then no o/p signal at all. Replaced with an as found
24C04 and same nothing out.
Probably too much of a workup to descramble those 9 lines to give even just
a monochrome image


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