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Post by misoman on Jan 29, 2023 16:02:11 GMT
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Post by misoman on Oct 30, 2022 15:21:06 GMT
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Post by misoman on Oct 25, 2018 4:02:12 GMT
I will tabulate some results when I get some free time. I realize this is a lot to ask, but once you're finished updating your VDC model (for the time being), would you consider a write-up on what you've learned about the VDC's inner workings? I'd even contribute financially for an article that fills in some of the knowledge gaps of the available documentation, particularly timing and ready flag behavior so that I can use the VDC more effectively.
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Post by misoman on Jul 7, 2017 4:21:11 GMT
This will probably win a dumb question of the decade award as I'm too ignorant of electronics to know whether this is practicable, but would it be possible to construct a circuit that takes the VDC composite signal that some use to display monochrome 80 column output on a TV or composite monitor, and add chroma to the signal? With the goal being to bump the display device into color composite mode and take advantage of NTSC artifact colors using periodic bit patterns. Here's an example with CGA 640x200 black and white: While you end up sacrificing resolution for color, you end up with some advantages. One being that you more or less get a 160x200x16 mode with no color cell restrictions using just a simple 640x200x2 bitmap. Or with good use of custom characters in text mode to represent the bit patterns instead, one could even do some decent fast animation. Interlace is even an option, which might provide some nice color blending capabilities. Sure, if you're going to treat the VDC as low res you can simulate 160x100x16 by using 8x2 color cells, but this doesn't need color attributes at all and would be usable by people with 16KB VDCs. Plus you don't lose half your vertical resolution. Anyway, I'm just curious if this is technically possible and how difficult it would be compared to projects like RGBI-to-VGA? And how would one go about choosing a good chroma value in the circuit to produce a nice palette? The one shown in the image above is pretty decent since it's close to the VDC palette to begin with, but as you can see from the article linked below the possibilities are pretty diverse. Can you think of a way a chroma choice could be communicated to the circuit by the C128 itself through the composite signal so that different palettes could be software selected? Yes, I understand that even if this would be possible, it's not very practical. For one thing, it'd be of no use for PAL users, which is an enormous downside. Still, I find the idea interesting. Inspiration for my question: 8088mph.blogspot.com/2015/04/cga-in-1024-colors-new-mode-illustrated.html(No, I'm not envisioning 1024 color VDC output, I'm just curious if we can give it a new 16 color mode.) Thank you for your time.
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Post by misoman on May 17, 2017 21:36:27 GMT
Do you have an updated link? That one no longer works.
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