MrPix

PM me about it and I’ll see you get one the first day.

I’m interested in all of it, if I can get the hardware cheaply. Also memory and carts too. I have tons of rom and sram.

Someone asked me about the possibility of designing an RGB adapter for the AY-3-8915. It looks almost trivially simple to do. What am I missing? In the table below, it looks like I just need to recreate the table using RGB values as an alternative output, and put that 3:3:3 or 4:4:2 output through three R2R ladders. Synch can be produces as H, V and CSYNCH too. From there, it would be easy to derive CLEAN composite, or S-Video output too. Would there be much demand for this? I did see someone else's very overly huge RGB adaptor by googling. I would be able to make something 1/4 the size of that. It would be economical.

I do have a library logic for separating CSYNCH into HSYNCH and VSYNCH. If there is a lot of demand for this, I can incorporate it. It's a 50c part.

My standard S-Video board has 4-pin mini-DIN for S-Video, composite RCA, and next to that an 8-pin mini-DIN with that exact pin-out. I'd also be able to supply the board unwired so people can do *whatever they want*

We can. Just remember the output is old school RGB, not VGA, and most newer VGA monitors won't be able to display it.

Ok, a big question now. Since this is an RGB output, what RGB socket to people most want to use? Do you want a 9-pin D-SUB, or a DIN socket, or a small PS/2 type socket, or what? Is there a particular type of monitor more of you use, where providing that socket will simplify things and allow cable re-use for the most people? What have you got?!

You proooooobably don't want to check your PMs then

You have really good instincts. All inner corners need to have a gentle radius. I think you're a natural. I'm looking forward to revision 0.2 (since this is still very beta... Isn't it? Or is it?

Hehe, yes I already do a lot of parts consolidation. Part of my feedback to Falonn was consolidation and clean up of capacitors. I also will change the board shape to reduce hole count, and minimize layer changes to reduce via count as these all have a cost too.

And the citrus3000psi board is 1/3rd the component cost. It’s only possible to do this because I’m buying more parts than I need to hit the price breaks. I’ll be investing about $2,200 or so in components, plus shipping. That doesn’t include some parts I haven’t priced yet. It’s a small risk, a huge investment, but worth it for the community. Y’all are getting old and your eyes are going! ;D

I never have crazy shipping rates. Within the US/Canada it would be probably around $5, and to the EU I would probably ship a bunch of them to someone there to reship them at local rates. Possibly through sellmyretro.com? As for kits, I've had a couple of PMs begging and imploring and explaining the error of my ways. Honestly, if you want to assemble one yourself I'll send you a kit. It's just that it will take longer to make the kit than the assembled unit, so it would cost the same. I have to label the tapes with the components so you know the values as they're just too small to have the values printed on. In that case, I will make up a set number of kits for the determined and foolhardy, and when they're gone they're gone. Assembled units will have a warranty and support. With kits, I would help as much as I could, but no warranty. Look again at the PCB image Falonn posted above. The components all fit into a half inch band. 13mm. The parts and board are *tiny*. Hehe.

A bit more info: My design will be a 4-layer board. It will only be available fully assembled - sorry kit makers - this SMD board has TSSOP parts and really needs automated assembly. Right now I'm collecting info about the layouts of boards that use the 9928/9 to know what shape will fit ALL boards without conflicts, and also to find out the connectors and pinouts of desired RGB ports for each model. There will also be an RGB to S-Video/composite add-on available as a separate plug in board to give very clean S-Video with dot crawl eliminated. I will not be offering an installation service, but I will direct everyone to Ruggers Customs if they want someone else to do the install. Installation requires the ability to disassemble, solder, fit the new socket (some cutting may be required) and re-assembling your machine. If you install it yourself it's at your own risk. I don't have a costing yet, but it looks like the board, tested, assembled and shipped will be around $35-40ish. Maybe a bit less. I'll do the best I can to keep the cost reasonable without compromising quality.

I've replied in PM as part of an ongoing conversation with Falonn with feedback of a couple of changes I'd recommend. They're only small 'perfectionism' things, mainly involving the debounce caps organization and a small issue with signal routing near U6:15. There will likely be a small revision to the board in a couple of days, so if you're planning to order the board from OSHpark you might want to wait just a couple of days. Meanwhile, I'm setting up for a production run of 250. There will be plenty for everyone who wants one. We'll also have a variety of RGB socket options for various machines. They will be economically priced.

This won't be a kit project - I think about 90% of hobbyists would have severe problems assembling it. I'll make it fit by using some very careful design.

It takes parallel input, converts it to a PDF then can directly print it via a USB attached printer and also save the file as a PDF.

The RetroPrinter solves this problem. https://www.retroprinter.com

Fairy knuff. Artifact I just wanted to drop here that this is an impressive amount of work and level of detail. I'm so relieved I didn't have to do this myself on my own workbench - I would have done a lesser job compared to you. I did get a new 'scope out of it, though, so that's good!

When you bypass L9, it seems the clock goes to pieces causing per line left/right shifts of entire rows. Most apparent in the white square and the left edge of the R.

Don't worry. I got you. The option board uses the AD725 to offer S-Video and clean composite (about the best I have measured in a sub-$150 device.)

I auditioned that chip, but rejected it for horrible dot crawl.

I have a large stock of AD725 from another S-video adapter design I did. It's neat. I was thinking of offering a header to the RGB socket that includes power, so this board could be connected and powered off the RGB adaptor. Give it time.

Aside from passing Y through the 4053, the only other changes will be values? In which case I will start on the schematic capture and PCB layout. Do you think this is evolved enough for me to start IC shopping?

Amazing! Where can I get DaveCAD?

Very exciting.