If you really want it to be 'compatible' with something else search for videos and pages on building an Apple II compatible with modern discrete components. Super neat resources for that out there.

But since you are already doing a BE6502, the 'Worlds Worst Videocard' is a pretty good place to ...

Thanks so much!

Thanks everyone here at 6502.org for helping both directly and with your past posts!
Without you all I would NOT have been able to do this:

https://www.youtube.com/watch?v=0glEfLZCwmc

I'm working on a proper writeup with details but please take a look:
https://github.com/NormalLuser/Ben-Eater ...

Thanks guys!
.rorg $1234 and .rend is exactly what I needed.
Don't know how I missed that in the vasm manual.
Worked great!

Hi all. I’m working on my Bad Apple! video decoder and have this version just about finished up.
One of the last things I wanted was a self contained ROM that boots right up to the demo.
The problem is that I have a little bit of self modifying code so I want to move some to RAM and I don't quite ...

Great result! There's a couple of things you can cheaply do with your counts - both your skip counts and your repeat counts. One is to apply an offset, so 0-63 becomes 10-73 or any other range which happens to work best. Another is to apply scaling, so 0-63 becomes 0-126, or combine both so 10-73 ...

Hey everyone!
An update on the progress I've made in my quest for FPS.
I just can't leave well enough alone and had to try to squeeze a little more performance out of this.
And I've finally found something useful to do on this project with basic self modifying code!
For whatever reason I really ...

Great result! There's a couple of things you can cheaply do with your counts - both your skip counts and your repeat counts. One is to apply an offset, so 0-63 becomes 10-73 or any other range which happens to work best. Another is to apply scaling, so 0-63 becomes 0-126, or combine both so 10-73 ...

53 Frames a second!
I have my new one byte encoder/decoder and am now pushing 53 frames a second with vsync off.
It has Run Length, Differential and Tri Pixel Encoding.
With Vsync the video plays almost perfectly in sync down to the second.
The one byte encoder has the average bytes per frame down ...

Steamboat Willie demo on my 6502..
https://youtu.be/8Jy-tLoXLFw

I wanted something to show off a few changes I made but wanted something different than Bad Apple while doing this testing.
Well, I made some optimizations realizing that since I always encode skips for every frame and there are 28 ...

Awsome project!
Have you considered using a FIFO like CD74HC40105 instead of registers? Edit.. You'd need to keep the parellel to serial register and put the Fifo in front using the Fifo Not Empty to decide to gate in another update.
You would still need to be mindful of sending updates too fast but ...

Once I think I can't take that further without a whole PIC or whatever in there if I still need more speed I should probably just move to Compact Flash?
http://forum.6502.org/viewtopic.php?f=4&t=2877

All my CF interfaces are bus-connected, ie, connect 6502's data bus directly to CF's data bus ...

What about an SPI EEPROM? Easier to setup and read and they stream really well.


I have thought about this. However I need 3 or 4 MegaBytes to store video and audio.
There are parallel chips that exist but with the shortage they seem to be hundreds of $$.
I can find some SPI chips but they are ...

I've had a custom circuit reading SD cards by SPI using a 4MHz clock to drive shift registers, and the card was happy with that. I have heard that some cards may require a slow clock speed during initialisation, but it may vary from card to card.

It's possible to use the VIA shift register to read ...

Once started the SD card will stream bits forever.
As long as you take into account a 10 byte CRC message every 512 bytes anyway.
Seems in this application the CRC message is superfluous. Any way to tell the SD card to not send it?


I know, it would be great.
From what I gather from a couple of ...