68kMLA Classic Interface

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Macintosh IIci Logicboard recreation
Posted by: Phipli on 2024-01-07 09:33:47
It feels like purists are going to scream at me for daring to suggest 'fixing' the IIci
Not sure there are many purists around here. Mine has a colour cycling power LED 🤣
Posted by: Arbee on 2024-01-07 09:57:41
I don't think purists would use a recreation anyway.
Posted by: bigmessowires on 2024-01-07 14:40:15
However, I don't like the cache slot. With schematics, it should be reasonably easy (famous last words!) to rewire it in a 'true' PDS'030 compatible with the SE/30 and IIsI
I don't think purists would use a recreation anyway.
With just a few small changes, you could also replace the 68030 with a Raspberry Pi!
Posted by: max1zzz on 2024-01-07 17:12:23
Another awesome piece of work 🙂 Pure tracing, or is there some associated schematics?
There is a full Schematic to go with it, I went with a traceing becuse if someone else has worked out the board routing why reinvent the wheel 🙂
Also, perhaps those 30-pins SIMM could be replaced by a pair of space-saving 72-pin SIMMs
Already on my radar, Will need some significant rerouting of the bottom of the board and proably require deleting the parity circuit (But how many people actually have parity boards, I couldn't even find a picture of one!). Will be looking at modifications once I have tested the stock boards 🙂
Posted by: max1zzz on 2024-01-07 17:13:36
With just a few small changes, you could also replace the 68030 with a Raspberry Pi!
Don't tell the purists but I have a IIci where I replaced the 68030 with a Ryzen 5 2600 🤣
Posted by: Trash80toHP_Mini on 2024-01-07 19:50:09
You are one SICK individual, which is, of course why you're one of may favorites amongst the rogues galleries here and thereabouts!
Rock on bro! 😁
Posted by: twelvetone12 on 2024-01-08 01:27:55
Ohhh fantastic job! The IIci was the first computer I've ever used, it was my father's and he used it up until 2002 or 2003. Very cool machine, I remember setting it up for dialup internet in 1994.
What did you use to trace the PCB?
Posted by: olePigeon on 2024-01-08 09:38:29
This is good news. I have at least two donor boards that I can scrap for parts, and two ATX to IIci adapters to use for power supplies.
Posted by: olePigeon on 2024-01-08 09:39:41
Already on my radar, Will need some significant rerouting of the bottom of the board and proably require deleting the parity circuit (But how many people actually have parity boards, I couldn't even find a picture of one!). Will be looking at modifications once I have tested the stock boards 🙂

Are we making a wish list? I vote for a 4th NuBus slot. 🙂

Also, I like the 30-pin SIMMs. My brick o' RAM is magnificent.
Posted by: robin-fo on 2024-01-08 09:46:02
Can I build this using IIsi donor parts? I have a spare, bombed board without case…
I‘d be happy without NuBus slots… 😉
Posted by: Phipli on 2024-01-08 10:45:41
Can I build this using IIsi donor parts? I have a spare, bombed board without case…
I‘d be happy without NuBus slots… 😉
There would be missing parts, the IIsi is sort of half IIci, half LC and a bit unique.

Wish they'd done more with that case. I'd have loved a Centris in that case.
Posted by: GRudolf94 on 2024-01-08 11:39:20
What did you use to trace the PCB?
I would assume Max is using SprintPCB, as that offers trace-over-background functionality.
Posted by: uyjulian on 2024-01-08 13:49:37
Nice I have some bombed boards I could use for ports.

Some additional ideas I'll throw in:

Integrate ram and e.g. zuluscsi on the mainboard
mini-ITX/ATX compatible layout
Posted by: max1zzz on 2024-01-17 09:32:20
Purple shiny things arrived yesterday 🙂
IMG_3156.jpg

Currently assembling them, might take a little while
Posted by: Phipli on 2024-01-17 09:42:54
Purple shiny things arrived yesterday 🙂
View attachment 68265

Currently assembling them, might take a little while
At least an hour 😉

Nice work 🙂 look absolutely amazing.
Posted by: robin-fo on 2024-01-17 09:58:33
Are you going to use stencils and solder paste?
Posted by: max1zzz on 2024-01-17 10:06:14
Nice work 🙂 look absolutely amazing.
Thanks 🙂

Are you going to use stencils and solder paste?
Nope, personally I don't like soldering PLCC or QFP parts with paste, I find I end up spending more time fixing bridges than if I just hand solder them. Will be hand soldering the lot 🙂

I was looking at getting the birdseed on the bottom PNP'd but it ended up costing too much for a prototype run, JLC don't have a very big library of "Basic" 1206 parts so it gets expensive quick
Posted by: Melkhior on 2024-01-17 10:32:46
Dumb question - are IIci boards only 2 layers? I can only see two colors (red/green) for traces in your original picture. That would explain the quite complex routing I see on your beautiful purple boards!
Posted by: max1zzz on 2024-01-17 10:36:53
The boards are 4 layers, Signals all on the outer layers with power on the inner, I have the inners layers hidden in those pictures as otherwise you would just see a solid block
Posted by: Melkhior on 2024-01-17 10:47:34
The boards are 4 layers, Signals all on the outer layers with power on the inner, I have the inners layers hidden in those pictures as otherwise you would just see a solid block
OK thanks make sense, such a complex board with just two layers seemed unlikely. The inner-for-ground-and-power setup is fairly standard, I should have guessed. So no margin for adjustment from that (6 layers is just too freaking expensive at JLCPCB, at least for now).
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