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Old 10th Aug 2022, 1:42 am   #96
Graham G3ZVT
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Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,725
Default Re: Modeline experiments

What seems to happen is this.
Any two out of the three VGA ports can be active.
They become active by seeing a monitor connected at boot up.
If three monitors are present, the on board port remains inactive.

So yes, in theory we could feed two TV signals from our ATI cards but we would only have the TVs from then on, and recovery would involve a reboot.


Regarding the monostables, I just took a look at mine, and the position adjustment is a 6.8k resistor in series with a 10k pot.
The pulse width has a 1k resistor in series with a 10k pot.

Pin 15 to VCC measures 9.5k and pin 7 to VCC measures 3.55k. My timing capacitors are both 4,700pF
I use these blue multi-turn pots, they cost next to nothing. and much better than traditional presets.
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