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The discontinued ICs include the XC9572XL used in the Floppy Emu. Fortunately I have a lot of them stockpiled while I work on a redesign using a different IC. I'm not too surprised that Xilinx is discontinuing these, but I am surprised that there's no alternative 5V-tolerant programmable logic...

I looked at the pinout for those 8-bit Apple TTL adapters and it's definitely out of scope for what the Sync-inator is intended to do, sorry. It's a physical adapter for DB15 to DE15 with an optional composite sync splitter, that much is in common. But an Apple TTL adapter would also need a...

Cool! How is the programming performed? What's the interface? Are you connecting a USB cable to the Pico and initiating programming with a custom application running on a nearby PC? Can the Mac continue running while the SIMM is being reprogrammed? Or do you have a Mac-hosted program that...

I don't understand the post office. Shipped from California, at this rate the beta hardware sent to Sweden will arrive before hardware sent to Indiana. pokes at mailbox with stick @NJRoadfan or @Arbee do you know where I could find the complete pinout for those TTL-level Apple II / Apple III...

Do you mean the Apple II? Wouldn't those also have a different physical connector than the DB-15 used on early Macs?

Thanks everyone, the first few beta units have been sent out today, but I'll look to get more made soon. Hopefully this will be generally available for everybody in about a month.

@Jockelill DM me your address and I'll get you one. @luRaichu I'll put you on the list as well, though I may wait a bit first to look for more people with older / composite sync gear to test. Thanks! Anyone else interested?

The BMOW Mac Sync-inator is finally ready for public consumption, and I'm looking for 3-4 beta testers. The hardware is free for testers, in exchange for you taking the time to put it through the wringer with your vintage Mac or Apple IIgs systems and video cards and monitors, and send me...

Thanks! Yes it's the CCL peripheral, and some variant of it has been appearing in many newer microcontrollers from Atmel / Microchip in recent years. Combined with the event system (also fairly new to this family) and some asynchronous timer capabilities, it's a pretty impressive toolkit for a...

I'm declaring the Sync-inator ready for public consumption. I've tested a million different combinations of monitors and video sources and it's finally good to go, four months after the adventure started with my Mac IIci and some Craigslist monitors that wouldn't cooperate. The current...

Off topic, "I can't locate a battery in the right slot" seems like an oddly anthropomorphizing error message. Are there are other examples from the classic Mac OS where the computer refers to itself in the first person?

With just a few small changes, you could also replace the 68030 with a Raspberry Pi!

Interesting, I've never seen that symbology before. I guess it's more of a layout hint than schematic information.

Those Bomarc schematics occasionally have conventions that I don't understand, or maybe they're mistakes. This one is also from the IIci schematic: What is the circled section trying to communicate? Something like: this trace is surrounded by GND? The same convention is used again near the...

Good news, bad news for Apple IIgs fans: the Sync-inator does work on the GS when you have a monitor that can handle 15 kHz, but it doesn't work the way I'd expected. Composite sync splitting of the 15 kHz GS signal doesn't work very well, but proves to be mostly unnecessary anyway. Here's the...

The sound chip creates the reset signal for the rest of the system. If you're getting a chime of death, that's probably fine. I think you're right that a system with no RAM will always get a chime of death, but I haven't tried it recently. Do you have another Mac that you could use to test the...

Good catch!! It looks like pin 50 of the 68030 is broken or shorted to pin 49. From a glance at the datasheet, pin 49 is +5V and pin 50 is NC, so I'm not sure it would make a difference though.

The 8-24 has a revision B that adds additional supported video resolutions. Is that also true of the 8-24 GC, or might this be a case of confusing two cards with similar names?

Is this the normal push-button power switch, or something custom? I'm not sure about this version, but the case itself is an integral part of the locking power switch mechanism on the IIcx and IIci. It doesn't work if the logic board is removed from the case. If this rack mount conversion...

I agree with others who've said a RAM problem is the first thing to check. You only need one RAM bank filled in order to boot, so you could try swapping around the sets of SIMMs in order to test them one at a time.