6502.org

Ed, I think you were right. Apparently I had kept my probes on 1x mode for...ever, and now that I put it on 10x mode, it no longer crashes when I probe the line.

But, I have discovered some incredible ground-bounce! Particularly with the address lines. Hm, interesting. And the further my probe's ground is from the signal I'm probing, the worse the ground-bounce is. How interesting! It's a whole new level of 'scope use that I never knew!

Thank you. New discoveries all the time.

Chad

Just an update:

Through the events of the VIA not being read from (near bottom here viewtopic.php?f=4&t=7506), I decided to solder it directly to the board in my prototyping area. I also soldered in a '138 and some transistors to make this updated to the latest revisions that I have posted on Github (here https://github.com/stevenchadburrow). Well, the '138 is just for this board, but it was a test to see if I could allocate different memory spaces for I/O devices, and I can very easily it seems.

So, the VIA runs both ways now, read and write, and my monitor program actually can now be used to interface with it directly. There are also pin headers for other I/O locations, as well as all of the pins used by the VIA. Lastly, I put in an SPST switch for the VIA's interrupts so that I can turn them off manually. This is more for prototyping than anything else. All in all, very very convenient.

I feel that I have now gained a great deal of knowledge of how things work and how to solder. How things work because I decided to solder the '138 to the board almost off-handed last night, and it worked the very first time. How to solder because, well, it's difficult to add and modify with a ton of huge bodge wires in the way!

I'm expecting my Serial VGA board (topic here viewtopic.php?f=4&t=7544) before the weekend, and I hope to post updates on how that works soon. Now that my VIA is working properly, I can easily interface new things like this without much effort.

Thanks everyone!

Chad

Woo! What's the big switch in the prototyping area for?