68kMLA Classic Interface

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Reverse Engineering the Macintosh Plus PCB
Posted by: volvo242gt on 2022-02-24 09:39:18
That's just because the floppy drive is not hooked up, for some reason the icon doesn't flash on the plus without a drive present
I think mine (the former tafkar Mac Plus) does... I'll check later today. It currently is driveless.

Another idea for a future revision would be to hack in the necessary code and to swap a SWIM chip for the IWM chip to provide Superdrive capabilities to the Plus board.
Posted by: max1zzz on 2023-02-05 14:56:45
Board layout, gerbers and scans are now on GitHub:
github.com

GitHub - max234252/MacPlus-Reloaded: 1:1 Reproduction of the Mac Plus PCB

1:1 Reproduction of the Mac Plus PCB. Contribute to max234252/MacPlus-Reloaded development by creating an account on GitHub.
github.com github.com

As with my other designs these are provided under a non-commercial licence but if you are a repairer and want to offer transplant services (or have any other commercial use in mind) please contact me

BOM will be added soon, It needs a little cleaning up first

I haven't updated the ROMinated board as I still need to get around to testing it....
Posted by: Iesca on 2023-02-05 15:38:00
Now that the board is reversed-engineered, would it be difficult for someone to make a new version of the schematics? Given that the ones currently floating around out there for the Plus are very low quality and hard to read.
Posted by: max1zzz on 2023-02-05 15:50:06
Now that the board is reversed-engineered, would it be difficult for someone to make a new version of the schematics? Given that the ones currently floating around out there for the Plus are very low quality and hard to read.
That is actually something that is on my list of things to do 🙂
Unfortunately that list is very long so if someone else want to have a crack at it please be my guest!
Posted by: al kossow on 2023-02-17 18:45:48
Now that the board is reversed-engineered, would it be difficult for someone to make a new version of the schematics? Given that the ones currently floating around out there for the Plus are very low quality and hard to read.
scanned from a blueprint I bought off eBay
Posted by: Iesca on 2023-02-18 00:28:11
Oh wow, what an improvement! Thank you so much!
Posted by: Jockelill on 2023-02-19 02:09:37
Fantastic work @max1zzz !! I recently started the task for making a new analogue board for the Plus, so first step was to remove all components and get a good scan. So here you go if anyone else wants to try it before I finish. I've also scanned the plastic cover. I also noticed the the scanner cut a tiny bit of the component side, I'll correct that when I'm back in office in early March.
Posted by: aihk on 2025-02-13 01:08:27
Super job, well done!!


Or even just a 50 pin (internal) SCSI header would be useful.

Something else to think about... the Plus can be a pain with SCSI devices, since it doesn't supply TERM POWER. I know @erichelgeson had to make some mods to his BlueSCSI to try and overcome that. Would be nice if that could be done to address that.. 🙂
I used your file to make plus, and there was a problem with the checkerboard.
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