digger wrote on 2020-05-26, 15:17:

I might be able to help you with a crucial piece of the puzzle here! 🙂 […]
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I might be able to help you with a crucial piece of the puzzle here! 🙂

Years ago, I asked people on the the Vintage Computer Forum whether they could help me obtain the so-called "Bus Correction Kit", an obscure aftermarket product for the Olivetti M24, which someone back in the day developed to fix incompatibilities in the M24 bus that would cause problems with EGA and VGA cards in that system, at least in some software. Forum member Chuck(G) had one of those kits, made pictures of it and made a dump of the PAL (or GAL?) chip. Another forum user named keepiru used those binary dumps and the pictures to actually recreate one. He offered to send it to me, but I didn't check the forum daily, so by the time I read his offer after some time had passed, I couldn't get ahold of him anymore. 🙁

However, the design files of the reverse-engineered recreation of the Bus Correction Kit can still be downloaded from that forum thread and could be used to make some new batches of this device.

http://www.vcfed.org/forum/showthread.p ... vetti-M24)

If anybody with the necessary skills is prepared to take up the challenge of having more of these bus correction kits produced, I would certainly get in line to order one! Getting EGA graphics to work on my Dad's Olivetti M24 has been this life-long dream and kind of a sacred Quest for the Holy Grail for me, ever since I was a kid. 😊

Maybe I'm blind, but I don't actually see design files, only some .jpeg pictures and a mention of gerbers, but none there...

If there are gerbers, this is very simple, just send them off to a PCB foundry. The rest is incredibly easy, just solder two sockets, a cap and a jumper header. I'd be willing and able to do that.
If there aren't gerbers it gets slightly more complicated. It's still a very simple design, but PCB design isn't something I've done yet (recently started a mature student degree course in electrical engineering, so will do so sooner or later 😉 ), and I'm most worried about the physical dimensions...

Speaking of the M24 and the Vintage Computer Forum, I just found this other topic where someone shared the design of the "M24-IDE", a variant of the XTIDE card that takes advantage of the proprietary 16-bot bus of the Olivetti M24. That is incredibly cool, since hardly any cards were made that could take advantage of it. If someone plans on a production run of those, I would be on board with that as well, of course. 😀

http://www.vcfed.org/forum/showthread.php?669 … 4-AT-amp-T-6300

Interesting indeed 😀

Btw, I still haven't gotten around to fixing my M24. My M240 does happily work - and output EGA too for that matter, but as that has a regular XT bus, it's not a challenge.

Today i have toyed with my m24 and obtained excellent results.

My MFM hard drive still works, but i've decided to try some xt-ide cards i've assembled.
I have 2 different kinds of "lo.tech" xt-ide cards: they work with the MFM controller unplugged.
The compact xt-ide works with the '8086' bin file at c800.
I had problems with the regular v.3 xt-ide.Didn't work with its '8086' bin, but when i used the offr566.bin, the 'padded' bios that was meant for the compact one, it started working!
I've decided using the compact version, since i have a couple.
Installed dos5 from a 360k floppy copy. Used the usual FDISK, format and sys c:, but i had to use also FDISK /MBR command, or else it wouldn't boot. 1gb CF ( 🤣 its too much!)

Then i needed to understand why my GO481 16 bit Vga card had b/w output.
I was convinced that putting this 16 bit card in the 8 bit slot was the cause, but i was wrong!
Jumpers on the motherboard are set to "ega" video card, and the card itself is my only isa Video Card that works in this pc (incidentally it's an Olivetti card, probably taken from a 286)

The only thing i could do was toying with the original Video card jumpers.(as you should know, the original video card links the expansion board and the motherboard so you can't take it out)

I've tried jumpers A,W3,W2, PC froze. When i tried messing with W1 the pc started, and all software has color Vga now. Games and everything. The jumper is currently set 1-2 which means 'controller disabled'.
Ill not touch a single jumper anymore on this board now! 🤣
Now i have a working Vga M24, i can use it with a regular monitor.

Then i tried my 'Snark Barker' (an 8 bit Sound Blaster clone) that i made myself, and an Adlib card. They both work!
I've tried 'em with Loom, Monkey island, and the SB with... Dr.Sbaitso...
I've decided to keep the Adlib tho, SB is a bit too much for 8086 i guess.

My main issue was the monitor,but now have a fully functional m24.