Figured out the palette. Turns out setting palette entries works better _after_ you switch video modes. 😑 Porting the scaler has also gone well, minus one issue with signed indexes. But this pretty much only works because I've cranked the emulation speed up on DOSBox so it can draw everything in vblank.

I have realized to my horror that VGA doesn't do a 320x200x256 linear framebuffer graphics mode where you can flip pages. Mode 13h utilizes all four planes in "chain mode", so the one page of linear framebuffer is all you get. If you want page flipping, you have to modify this to a sort of interleaved planar mode where every fourth column of pixels lives in a plane. And to switch which plane you're writing to you have to twiddle some VGA registers, which are themselves abstracted behind address/data I/O port pairs. I knew the PC platform was a pile of bad hacks but I am still somewhat aghast that people put up with this. The good news is, this gives you some interesting data pathway tricks you can use to perform faster fills and copies. Which will probably be quite useful, actually.

So now I get to completely rewrite this...

Well this is definitely... something. Palette's all screwed up on the sprite. Not sure what's going on there. But the lines look nice.

Getting to grips with VGA and OpenWatcom.

The board is easy enough to remove. But the connections to the neck board are not removable. :/ Also interesting, there’s a single loop of wire around the flyback core. Some kind of feedback mechanism?

Cleaning up this old monitor. Viewsonic Optiquest Q51. It was sitting in a barn for a while, but it worked last time I turned it on. It just needs a bath.

Apricot sorted, let’s look at some stuff I got from the free pile. First up is this cable, which looks like your usual 25 to 9 pin serial cable. Interestingly, it has “Made in W. Germany” printed on both ends.

Look a little closer and you realize it’s male on both ends. This isn’t a PC modem cable.

It does indeed seem to be a head pressure problem, as gentle pressure on the arm gets it to boot properly. The loading mechanism itself seems to be working fine. The only thing that clamps the head seems to be a spring. I need to read more of the manual to see if this is adjustable. I imagine it is somehow - pretty much everything on these early drives is adjustable (and sometimes needs it). I also want to get a scope on the read amp to see what that looks like.

Anyway, taking a closer look at this OA-D32W from the Apricot.

There we go. Properly working now. 🫠 Not only had I wired it backwards, I also removed a part that was important.

I was going to make more Spite Sprites, but I think that’s about all I can take for tonight. I’ll see y’all at load-in.

Got this whole thing wired up, started testing. GUESS WHICH DUM DUM WIRED IT UP BACKWARDS?

I don’t think I’ve mentioned this lately, but it’s a week and a half to #VCFMW (https://vcfmw.org/)! I’ll be at table B521, surprisingly near to the entrance!

I’ll be showing off the Apricot Xi, a Toshiba T1200 running my prototype MFM emulator, and an Amiga 500 running my Spite Sprite composite/S-Video adapter and a converted PC mouse. I’ll be selling a few Spite Sprites and mice (if I can get any of them to work 😫).

Hope to see you there!

Looks pretty cool so far. :)

One of the other things I got is a “transition roll”. For a little less than a regular roll (not enough less IMO), you get a reject roll during a color changeover. This one is mostly clear/natural, then it seems to turn translucent green. Gonna print some Amiga video connectors with it and see how they look.

Interestingly, this one claims a temperature range of 220-235C, where the beige’s lower end was 200C. Printed Solid says they make it in-house, so I assume this is all the same formula. I wonder if the beige was just mis-marked.

I’ve also gotten some Jessie Beige 500, which is supposedly a color match for the Amiga 500. So some of these will be in the proper beige. :D

As an aside, I am #3dprinting these hard-to-find 23-pin D-sub shells. I’m actually using crimp contacts in them, since they’re still available (even new if you want to pay $0.40/contact - I got these from a surplus seller). The contacts push into the shell, and the crimp tails are soldered to the board. The shell is also has a retention flange that prints at an angle so the shell can be printed without supports.

The parametric model is here: https://dominionofawesome.com/obj/parametric-dsub/. If you’re looking for contacts, these are TE (formerly AMP) 66503.

One last thing, a little pixelated heart. This cruder model worked well enough, but it never flows enough to get rid of the voids. I started it by melting in little bits with the heat gun, then finished it in the oven.

Also this mold had epoxy/urethane/pigment residue on it, which baked off in the oven. So I guess that’s in my lungs now. :[

Presumably I could turn this stuff into filament but it’s hardly worth the effort. Flattened out sheets of it would probably work well with vacuum molding.

Shredded some more and tried it in a smaller, more detailed mold. Just heated this one with a heat gun since it was so small. Turned out not great, but I’m not too surprised by that.

Did I immediately try again with a silicone mold? Heck yeah.