archive.worldofdragon.org

robcfg wrote: ↑Wed Nov 29, 2023 7:57 pm Have you considered implementing a full Dragon on something like the Tang Nano 20K or similar?

Well, no time soon I imagine. Aren't there already "mister" setups for coco/dragon?

I'll just add that without a testbench that Stewart whipped up, fixing that would have taken a _lot_ longer, so thanks a lot, Stew!

http://www.6809.org.uk/tmp/samx4-wip/silky.mp4 I'm not especially keen on what I had to do to make that work (delay video mode register setting by two full cycles!), but work it does. So bar it turning out that it's screwed something else up by doing that, I'll try and prep the source etc. by the w...

After a note from Stewart, the refresh tester output seems to be fixed (and along with it the transition from slow to actually-fast mode).

Still not managed to figure out the glitch glitch, but I figured I'd test it with Phill's diag cart.

At first it completely failed! But once I removed the special-casing of $FF3x:

Ah, so this is where all the fun is happening! That's awesome :) I could be wrong but I think the majority of 256K drams had 8 bit refresh. Yeah I spotted that but it’s almost no extra to do 9. I'm curious to know if the logic to recreate the glitching is using up much resource or if you can get so...

http://www.6809.org.uk/tmp/samx4-wip/glitchy-less.mp4

Getting there. Still a slight wobble

99... and yeah that's with the banker board registers and 9-bit refresh (overkill, i know, but you only save one cell cutting it down to 8)

Meh. My glitching is glitching:

http://www.6809.org.uk/tmp/samx4-wip/glitch.mp4

Macrocell usage down to 111 though (98 with compact FSM!) as I realised I was being dumb with a few things.

That's super cool. Really hope the density option pulls back a load of macrocells, as some headroom on this design would open up some amazing possibilities. Afraid to say it ends up using more somehow ;) Of course if you were going to take this and use it for a more modern recreation, you'd rip out...

Edit: it's released now :) I'll post this here too... Working on a SAM replacement - not as a product really, more to prove the concept and work out the bugs so it can be used in future designs. At first I thought the reset detection wasn't working, but after bodging around that I put things back as...