Author Topic: Research into CV1000 Blitter  (Read 604 times)

Offline buffi

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Research into CV1000 Blitter
« on: January 01, 2023, 02:55:17 AM »
Thought I'd post this here as well, since there might be interest here.

I spent some time doing research on how the CV1000 Blitter works. There's a pretty long doc describing it here.
https://buffis.com/research/cv1000-blitter-research/

It's not fully complete (see future work section), but this should cover most of it.

Offline SuperPang

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Re: Research into CV1000 Blitter
« Reply #1 on: January 01, 2023, 08:56:19 AM »
My brain hurts.

Offline buffi

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Re: Research into CV1000 Blitter
« Reply #2 on: January 01, 2023, 01:02:00 PM »
Mine too

Offline EOJ

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Re: Research into CV1000 Blitter
« Reply #3 on: January 01, 2023, 06:07:43 PM »
Very impressive, as usual, buffi! Your pdf reads like an article in an academic journal.
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Offline buffi

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Re: Research into CV1000 Blitter
« Reply #4 on: February 28, 2023, 03:20:45 PM »
As a followup to this:


I did my best to make adjustment for the MAME driver to have it behave similar to the actual hardware, but need people to test it out to see if there's anything weird here, or if it seems good to you.

This only change here is for the Blitter logic, which means that CPU slowdown (which is the majority of CV1K slowdown) is not changed here.

To help out:
- Grab the modified binary at: http://site.buffis.com/mame/ and test it on CV1K games
Alternatively build it yourself from: https://github.com/buffis/mamefork
- See if this seems more accurate to actual PCBs compared to regular MAME, and if theres any weird things happening.

IMPORTANT
CPU slowdown is still the majority of slowdown, so I'd recommend experimenting with CPU% slider in combination with this (try 50% or 60% or something, I dunno). Its not an accurate representation of CPU slowdown, but it will be closer than nothing.

Offline EOJ

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Re: Research into CV1000 Blitter
« Reply #5 on: February 28, 2023, 03:59:50 PM »
Pretty cool update! I use a Mac now, so unfortunately I can't try it out myself.
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