Video driver thoughts

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PaulJ
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Re: Video driver thoughts

Post by PaulJ »

Forgottenmyname wrote: Tue Nov 27, 2018 8:18 pm Ok will get cracking now.
Be interesting to see if yours has the same issue. Just checked the mail and nothing.. :mad: :mad: To bad we don't have transporters.. Can't wait. :cry: :cry: :cry:
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exxos
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Re: Video driver thoughts

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Icky wrote: Tue Nov 27, 2018 9:05 pm First item between Falcon and board schematic

Falcon has pull up R503 on pins 15 & 26. Board schematic goes straight to Vcc
Its not a pull up as such, just series resistor with Vcc to power the analoge section of the chip... True 10R may be better, but I wouldn't have expected to be this much chaos without it.
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Icky
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Re: Video driver thoughts

Post by Icky »

exxos wrote: Tue Nov 27, 2018 9:08 pm
Icky wrote: Tue Nov 27, 2018 9:05 pm First item between Falcon and board schematic

Falcon has pull up R503 on pins 15 & 26. Board schematic goes straight to Vcc
Its not a pull up as such, just series resistor with Vcc to power the analoge section of the chip... True 10R may be better, but I wouldn't have expected to be this much chaos without it.
Other interesting item is DVCC1 & DVCC2 plus DGND1 and DGND2 don’t seem to feature in the Falcon schematic.
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exxos
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Re: Video driver thoughts

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Icky wrote: Tue Nov 27, 2018 9:13 pm Other interesting item is DVCC1 & DVCC2 plus DGND1 and DGND2 don’t seem to feature in the Falcon schematic.
Odd... must be there somewhere... its a the digital power supply to the chip, so doubt it would work without it.
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Re: Video driver thoughts

Post by exxos »

I guess you could swap out those 33R's in the RGB driver lines for 75R (or 68 or something around that value).. Maybe the colours are saturating causing the false colours :shrug:
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Icky
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Re: Video driver thoughts

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exxos wrote: Tue Nov 27, 2018 9:22 pm I guess you could swap out those 33R's in the RGB driver lines for 75R (or 68 or something around that value).. Maybe the colours are saturating causing the false colours :shrug:
Yes. The data sheet has 75R in series after the large caps and also a 75R pull down.
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Re: Video driver thoughts

Post by exxos »

Icky wrote: Tue Nov 27, 2018 9:29 pm Yes. The data sheet has 75R in series after the large caps and also a 75R pull down.
The 75R pull down is inside the monitor (after the cable)
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PhilC
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Re: Video driver thoughts

Post by PhilC »

Ok, so I have a few dodgy sockets on my STF, which is not helping, so I get to the TOS ver screen and it's white with b;ack writing as it should be.

Will try and get it to boot to desktop asap.
If it ain't broke, test it to Destruction.
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Icky
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Re: Video driver thoughts

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Forgottenmyname wrote: Tue Nov 27, 2018 9:40 pm Ok, so I have a few dodgy sockets on my STF, which is not helping, so I get to the TOS ver screen and it's white with b;ack writing as it should be.

Will try and get it to boot to desktop asap.
Sounds promising
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Icky
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Re: Video driver thoughts

Post by Icky »

Icky wrote: Tue Nov 27, 2018 9:29 pm
exxos wrote: Tue Nov 27, 2018 9:22 pm I guess you could swap out those 33R's in the RGB driver lines for 75R (or 68 or something around that value).. Maybe the colours are saturating causing the false colours :shrug:
Yes. The data sheet has 75R in series after the large caps and also a 75R pull down.
75R just makes it even more darker and the border is still black
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