Very interesting look at the difference between CGA and VDC capabilities! The VDC doesn't get much love so thanks for putting this together :D

Awesome video. We need more VDC videos. Thanks a ton and I hope you create more.

Nice video 👍 Subscribed. Looking forward to watching your EGA on the C128 video next.

Excellent video! Great step by step explanation. I appreciated the use of the vcd basic as a teaching aide.

About halfway through I was thinking this was a really complicated way to display 160x100x16 on a C128 lol, but being able to use the actual DOS content files on a Commodore is invaluable with connecting both platforms in an online environment for example. Really impressive stuff, neat how you got past the common-color restriction of Commodore hardware. I quite enjoy the hybridization of both platforms, like that CGA Composite Artifact Color option that approximates the C64 color palette.🙂

18:29 A much more efficient way to do this doesn't use strings at all: VMW AP, CL(INT(B/16))*16 + CL(B AND 15) The INT() is only for clarity and isn't even needed, since subscripts will be 'integerized' anyway.

It's amazing how big a CGA card is compared to the C128 CDV chip and RAM.

Very nice! One further optimization you could do is to fill the entire bitmap with %00001111. If two pixels are the same color, just set the attribute to the same color for both foreground and background. This way you can clear the bitmap with fast block fills of %00001111 and only have to individually set the color attribute RAM bytes. Going beyond that, there is also a double-width mode with which you can do theoretically do a 320x200 mode, which only takes up 8000 bytes of bitmap, and then treat it as 160x100x16 as here. I can't recall what that does to the color attributes though. There's also something in my memory about timing weirdness in double-width mode which can result in it requiring doing a slightly smaller horizontal width. So in actuality it might end up being something strange like 304x200, leaving you with 152x100. I'm without a C128 at the moment (but expecting to have one again soon) so I can't reliably experiment to reproduce the mode. It's also entirely possible that I just wasn't adjusting something correctly and could've gotten 320x200 working reliably with different settings. Even with the VDC's limitations compared to the VIC-II's strengths, I still find it a fascinating chip, and think more could've and would've been done on the graphics and gaming side in the 80s and 90s if people had understood it better. It's great to see people like yourself doing videos like these, and I hope it'll inspire more people to see what they can make the VDC do. One more thing regarding the double-width mode is that since it reduces the bitmap to only needing 8000 bytes, I wonder if the mode I described above could be done on the 16K chip? With attributes taking up 8000 bytes, we'd be at 16000 total. Seems like it could be doable, but I may be missing something that would change the math.

Warum ist dieses Video in Englisch während die vorherigen in Deutsch waren? Bin ein wenig verwundert 😅 Trotz alle dem wieder sehr informativ und interessant. Mir haben auch die vorherigen Videos sehr gefallen.😊

1:50 This is wrong. CGA can display 16 colors in high res. Generally though, it is limited to color cells in alpha numeric mode (displaying the built in fonts). The color data only takes 4 bits per cell and there are only 2k cells.

Schade das die jetzt auf Englisch sind😔😔😔 Englische Videos gibt es genug.