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Re: Q40/Q60
Posted: Mon Mar 25, 2024 11:50 am
by Derek_Stewart
Peter wrote: ↑Mon Mar 25, 2024 10:24 am
Derek_Stewart wrote: ↑Sun Mar 24, 2024 10:48 pm
There is a problem with the Q60 VGA video output, which does not give a clear video output in 1024x512 HiColour mode, on a modern LCD monitor
This is such a tragedy. At design time, it was simply not foreseeable that flatscreen monitors would no longer have multisync capabilities.
I have spent countless hours on this, but there is no fully satisfying solution.
A clear video picture is possible by a replacement PLD that generates 1024x768 resolution. But it keeps the lower part of the screen black and displays only 1024x512 in the upper area.
Derek_Stewart wrote: ↑Sun Mar 24, 2024 10:48 pm
I am looking into a ways of video signal conditioning to to suit moden LCD monitors.
It has been said that OSSC converters can provide that, if they are well tuned. But one has to be careful about the various variants.
Also I find them clumsy and expensive.
The OSSC is a very comprehensive open source video converter, but is hard to make, the pre-made converter boards are quite expensive.
I might have a go at making one.
Re: Q40/Q60
Posted: Thu Apr 11, 2024 10:27 am
by ones' complement
For those c
Raven something like a Q60 ?
Re: Q40/Q60
Posted: Thu Apr 11, 2024 12:35 pm
by XorA
It has been said that OSSC converters can provide that, if they are well tuned. But one has to be careful about the various variants.
Also I find them clumsy and expensive.
I have tried OSSC and gbs-control on Q60 and I could not find a setting on either that would successfully display the full Q60 screen!
Re: Q40/Q60
Posted: Thu Apr 11, 2024 12:49 pm
by ones' complement
XorA wrote: ↑Thu Apr 11, 2024 12:35 pm
It has been said that OSSC converters can provide that, if they are well tuned. But one has to be careful about the various variants.
Also I find them clumsy and expensive.
I have tried OSSC and gbs-control on Q60 and I could not find a setting on either that would successfully display the full Q60 screen!
Thierry's settings appear to give full Q60 display
http://qdos.free.fr/monitors.html (see
http://qdos.free.fr/files/OSSC.txt)
Re: Q40/Q60
Posted: Thu Apr 11, 2024 1:10 pm
by Peter
Many thanks for the link. Curious if someone gets it to work on an up-to-date OSSC.
Also to the "Raven" info. Funny, he uses ISA bus and old-fashioned SIMM sockets just like I did in 1997.
Did you find any info about the graphics?
Re: Q40/Q60
Posted: Thu Apr 11, 2024 4:31 pm
by ones' complement
Peter wrote: ↑Thu Apr 11, 2024 1:10 pmDid you find any info about the graphics?
No, anticipating when it's on github. Guess would be graphics card in ISA slot.
Re: Q40/Q60
Posted: Thu Apr 11, 2024 7:44 pm
by Peter
ones' complement wrote: ↑Thu Apr 11, 2024 4:31 pm
Peter wrote: ↑Thu Apr 11, 2024 1:10 pmDid you find any info about the graphics?
No, anticipating when it's on github. Guess would be graphics card in ISA slot.
ISA graphics Would also be a "solution" for the flatscreen monitor problem with the non-standard Q60 video output.
I never seriously considered that because of the much lower performace compared to the fast 32 bit dualport VRAM directly on the CPU bus.
Re: Q40/Q60
Posted: Thu Apr 11, 2024 7:59 pm
by Artificer
Peter wrote : Curious if someone gets it to work on an up-to-date OSSC.
Hi Peter, I bought an OSSC Kaico v1.6 scan doubler from Amazon for my Q60 during lockdown. Yes it was a bit pricey but I wasn't able to spend on much else, and if you think about the price of the scan doubler to what I paid for the Q60 20 or so years ago which I think if my memory is correct was around £700 it doesn't seem unreasonable to buy one to keep the Q60 going. I have used Thierry's settings with a cheap flat screen and while not perfect it is definitely usable.
Re: Q40/Q60
Posted: Thu Apr 11, 2024 8:17 pm
by Peter
Artificer wrote: ↑Thu Apr 11, 2024 7:59 pm
I have used Thierry's settings with a cheap flat screen and while not perfect it is definitely usable.
Many thanks for the info and for posting the pics. Not sure I would be satisfied with the OSSC.
Re: Q40/Q60
Posted: Thu Apr 11, 2024 8:27 pm
by pjw
Peter wrote: ↑Thu Apr 11, 2024 8:17 pm
<> Not sure I would be satisfied with the OSSC.
Same here. If the photos are an accurate representation it is not something I could work with. Sorry.