Search found 1346 matches

by sixxie
Fri Dec 22, 2023 11:40 am
Forum: Dragon Hardware
Topic: SAMx4 1.0
Replies: 1
Views: 9641

SAMx4 1.0

So thanks to lots of testing by Pedro Peña across his CoCo collection, SAMx4 now supports 4K and 16K ram sizes (and the extra 16K ram size in the '785). https://www.6809.org.uk/dragon/samx4/ Pedro's also designed a smaller version of the board, which is in the "rockyhill" branch in the gitlab reposi...
by sixxie
Tue Dec 12, 2023 8:16 pm
Forum: Dragon General
Topic: Getting XRoar (or anything else) to save as ASCII
Replies: 3
Views: 12848

Re: Getting XRoar (or anything else) to save as ASCII

I've got a .CAS file with a big BASIC program in. I'd love to edit it on my computer. So I thought, simple, I'll save as ASCII from within XRoar - but, actually, can I do that? I can do a CSAVEM"STUFF",A - but it's still padded with a bunch of CAS stuff. So what's a nice simple way to get a BASIC f...
by sixxie
Fri Dec 01, 2023 2:15 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

Right. This works for everything odd I can find to throw at it. So at the risk of triggering a really obvious realisation, here's the current state of play, with downloads and what-not:

http://www.6809.org.uk/dragon/samx4/
by sixxie
Wed Nov 29, 2023 9:29 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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?
by sixxie
Wed Nov 29, 2023 5:42 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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!
by sixxie
Wed Nov 29, 2023 4:56 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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...
by sixxie
Sun Nov 26, 2023 10:00 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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).
reftest.jpg
reftest.jpg (115.19 KiB) Viewed 63511 times
by sixxie
Fri Nov 24, 2023 5:34 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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:
diag.jpg
diag.jpg (105.78 KiB) Viewed 63537 times
by sixxie
Wed Nov 22, 2023 12:32 pm
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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...
by sixxie
Tue Nov 21, 2023 10:12 am
Forum: Dragon Hardware
Topic: SAM replacement - there!
Replies: 16
Views: 130604

Re: SAM replacement - nearly there

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)