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Like a splitter that makes two PDS slots from one? If the ethernet card uses DMA (I think many of the SE/30 ones do), I think there would need to be a bit of logic on the board to arbitrate between the two cards for memory accesses. If both cards assert /BR (bus request) at the same time, some...

By the way, in case anyone is wondering, these address and data lines I've routed in the image aren't fast enough to need length-matching. The entire length of the PDS is like 10 cm, and the signals will propagate at 60 picoseconds per cm or so, so the entire length of the PDS is traversed in...

Well this is new hardware development. Back in the day, logic cost more and they didn't have the luxury of accelerating the Macintosh with a custom-programmed 68000 emulator. There are some restrictions when you're running a real 680x0 that don't have to exist when you program a modern CPU or...

As long as a NuBus card can access video memory/VRAM, read the ROM, and access the peripherals (chipset and NuBus), I think it's doable. I dunno anything about NuBus though, other than that it's 32-bit, A/D multiplexed, and multi-master. The emulator is designed to use mostly its own RAM anyway...

I don't think I'm going to be able to do a card that works on both Plus and SE PDS, though. It just isn't cost-effective. There's not enough room for a bunch of level shifters and 3 TQFP-100 chips in between the paralleled PDS and 68000 DIP-64. I could do it in 6 layers, I think, but then that...

Rather than the IIci slot, why not NuBus? A NuBus card might have a bit less bandwidth than a PDS card but would be compatible with a dozen models. The cards could programmed to speak either NuBus or 68030 bus, selectable by a jumper. The pin layout of the Euro-DIN 96 would be for NuBus, but...

Can a PLCC device go in the socket upside-down? What does the socket on the bottom for the Classic look like? There is a bit of a problem. I have to have a lot more circuitry on my board than on the MicroMac board, which has some severe space constraints. I can only expand it to the left. If...

Alright, I get it now. I was confused about how traditional accelerator boards were structured, thinking they replace the 68000, not understanding the installation method, etc. You're right, it's all electrically the same as the PDS (duh, the PDS is in parallel with the processor). The only...

Here's the patent: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=4907976.PN.&OS=PN/4907976&RS=PN/4907976 Peter Killcommons is the inventor, hence the Killy Clip name. I'm...

I'm liking the idea of designing the DIP-64 Killy Klip. Designing the body and having it 3D printed is the easy part. The hard part is finding the right contacts. They've gotta be fat and kind of rolled or V-shaped where they touch the 68000's legs, but long, straight, and thick enough on the...

Screwing around with placement of components... the Mac SE PDS board shape specified in Designing Cards and Drivers for the Macintosh Family is huge. It's gotta be wide to be held up by the screws on the left, and it's also gotta be tall to have its connectors in the right area. Once I get...

No lol please argue with me. I want my effort to be best spent. Some new factors are influencing my decision about it, and I think I oughta add compatibility with as many 68000 compacts as I can. I realized about the SE/30, there's no point to do the schematic now, since the 68030 emulator...

Since I'm halting work on the SE/30 schematic for now. I'm moving on to the board for the SE. Maybe it will pick up 128k-Plus and/or Classic compatibility eventually, but I am counting more on just doing another board for those. More boards means more work, but also routing a board with a bunch...

Actually, I change my mind. Supporting the 128k - Plus is more important than supporting the SE/30, right? So maybe I should drop SE/30 entirely and support all the 68000 compacts. That's easier than supporting 68000 and 68030.

No idea. I have decided to put SE/30 on hold for now as well. The SE design is too young and unstable to turn it into a "master schematic" and fork that for each supported machine. That's what I was trying to do in the past few days, but when the schematic is changing so fast, that's a pain.    ...

Thanks, but no thanks. Like I said, I don't have time to do a board for IIci, but anyone is welcome to try to adapt what I have once I've made more progress. It's also a little early in the project for me to be accepting hardware donations lol, maybe once I have some kind of proof-of-concept...

Oh, cables. You mean the flat-flex kind? I dunno much about those. I was just going to mount the connector onto the accelerator board, and then the display sub-board would mate to it and be secured with a few screws. No cables, just the connector sockets mating the boards directly. My...

I think it should be very straightforward to port the schematic for SE/30 to the IIci's cache slot. It has basically the same signals as the SE/30 PDS. Of course, someone else has to design the board... I just don't have time to do it, and nor do I have a IIci. For the rest of the Mac II series...

The picture I posted wasn't of the exact series I'm using. What I plan to use is from the Hirose DF40 series. They're also used in the Snapdragon modules I'm looking at. Here's a link to the series on Digi-Key...

Version 2 of the Mac SE accelerator schematic is done. I've attached it to this post. SE/30 will be done tomorrow or Friday. Maccelerator-SE.pdf This version is a bit transitional, in that it uses the Variscite Dart 410 module, when I actually plan to use the Intrinsyc Open-Q 410. I just can't...