44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Hardware Hacking, Programming and Game Solutions/Cheats
linville
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by linville »

Cool, thanks!
linville
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Joined: Mon Feb 13, 2012 11:01 pm

Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by linville »

Hmmm...well, xroar seems to execute the unchanged 44-color (and 8-color) code more-or-less correctly, even with PAL configurations. I had expected that the extra horizontal sync pulses inserted to turn the NTSC-compatible output of the 6847 into a PAL-compatible signal would be visible through the PIA-controlled interrupt line, and would therefore need to be accounted for in the timing code. Maybe that isn't the case?

I definitely need someone to try this code on a PAL Dragon or CoCo (or both)...
zephyr
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by zephyr »

I'm quite busy ATM, but will try them for you if no one else tests them over the next few days.
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robcfg
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by robcfg »

If you can provide a .CAS or a .VDK/.DSK file with the test program, I'll be glad to test it.

Actually due to my setup, a .CAS file would be better.

Best regards,
Rob
linville
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by linville »

There are WAV files available already. Have you tried those? The xroar emulator seems to consume them FWIW.

What is your setup? It seems like a WAV file would be more friendly to loading on a real machine?

What tool do you use for building CAS files? The cecb tool from Toolshed doesn't seem to want to cooperate...
zephyr
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by zephyr »

Attached below are .CAS conversions (XROAR) of all the .WAV files for Robcfg, or anyone else would like to test them.
Attachments
44_colour_vdgtricks.zip
(64.43 KiB) Downloaded 224 times
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robcfg
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by robcfg »

Great, thanks!

I'll try to test them today when I come back home.
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robcfg
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by robcfg »

Good evening!

Here you have the result of the test programs on a real Dragon:

Paltest1
Image

Paltest2
YouTube Link

Testflip44
YouTube Link

Testg6c8
Image

Testsg24
Image

The Paltest2 and Testflip44 do flicker more than you can appreciate in the video, but also the effect is a bit better.

If you need to do more test, I'll be glad to help.

Best regards,
Rob
linville
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by linville »

Awesome! Thanks for the testing and the pics/video! The effects look more-or-less similar to what xroar showed.

It looks like the timing code is actually working, even though it thinks it is running on NTSC. I guess the extra hsync signals inserted for adapting to PAL video aren't visible to software on the CoCo/Dragon?

The flicker is a bit unavoidable, given the technique used in the paltest2 and testflip44 programs. I imagine that the flicker is worse on the 50 Hz PAL displays than on the 60 Hz NTSC displays. It is less than ideal, but I don't know that it can be "fixed" either... :-(

Anyway, at least I know that you guys can run the code as-is! Hopefully testg6c8 is impressive enough to make-up for the flicker of testflip44? :-)
linville
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Re: 44 on-screen colours from a CoCo 1/2 or Dragon 32/64

Post by linville »

I posted some pics of my NTSC CoCo displaying a variety of other images in 44 colors...

http://www.facebook.com/media/set/?set= ... 13314f06c9
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