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A final important update to my 20F PSU version. Wouldn't you know, I made a whole bunch of stupid mistakes.

1. The AC mains to 12V DC PSU unit was inserted the other way around in the schematics.

2. The PSU fan pins had been switched around.

3. I had used the wrong (smaller) footprint for the ATtiny in the schematics.

4. The ATtiny code had switched the Power Button and OS traces around.

In regards to programming an ATtiny for use on the board, I found buying the Digispark USB ATtiny thingy to work well. It is quite cheap, can be programmed directly by plugging into a computer and using the Arduino software, with appropriate module installed. Then I just soldered the ATtiny off of the USB board and soldered on the PSU.

The above are now fixed in the attached files.

Since printing the first revision boards cost me dearly I chose not to get the updated one made, and instead I worked around the mistakes, and can confirm it works in my 20F.

The old girl has life once again, after many, many years. Now I can shove it back into storage, never to use it again, since I have other fully functioning Towns models.

Interesting. I bet some really impressive graphical tricks could be pulled off by clever usage of this obscure mode.  Wonder if any existing games did something with it. The X68000 is so full of little unexplored niches like this. It is truly a shame that the platform did not enjoy the popularity of mainstream console platforms to warrant an entire army of game coders trying to wring every ounce of power out of it, like they did with the Famicom, PC Engine, Mega Drive and Super Famicom. One can only wonder.

Some years back someone asked me how special priority mode works and I was in hell so I never got back to them but I did make a document about it.

So here's that, if you're wanting to do weird fancy stuff with graphics layers it's interesting.

Since all my consoles are in need of a recap, I've started opening them and documenting what's inside.  I've created a wiki page that lists them all:

https://gamesx.com/wiki/doku.php?id=repair:capacitor_lists

You are of course encouraged to help me add to this, or tell me how it can be improved.  ^__^

Quote from: Cyothevile on April 06, 2025, 05:30:30 AMI think some of the ram could be faulty

Thank you for the tips but it was probably the SRAM, i desoldered the old one and placed a compatible SRAM that i used for the X68000 and i got the FM-TOWNS booting some times. Then i desoldered the new SRAM for having the original chip, but i destroyed some pads and without schematics i can't repair it, so used for spares. At least now i've a working Fresh thank to the cd-rom of the donor's FM-TOWNS II.

I think some of the ram could be faulty

You're using the wrong service to buy from Japan stores. Buyee is to buy from auction sites, it's not good to buy from stores directly that have time sensitive events. What you need is a service that gives you a local address to ship to, but they don't buy on your behalf - you buy from the store using your credit card directly with no middleman.  shipjp.com is what I've used with great success.

Quote from: gerowave on April 05, 2025, 10:05:46 AM/img]

My PCB has arrived! Yeah!
...how do I use HxC connector?

HxC connector is left from previous version without floppy emulation, now it's only for testing/future purpouse. You could not solder IDC connector at all in HxC side

My PCB has arrived! Yeah!
...how do I use HxC connector?

I fixed up the Saturn mod page today, where it seems like the jumper 6/7 codes were out of order.  For sure they didn't match the Korea-region Samsung Saturn I'm working on, so I updated them under the assumption that the console was right and the wiki was wrong.

If anyone spots any wrongness on the page, please do update it.

https://gamesx.com/wiki/doku.php?id=imports:sega_saturn#the_country_codes