FINALLY! Got it to work. 512K Mac with Internal SCSI!

[olePigeon]

I finally got my hack to work.  This will also work with a 128K.

I have some sort of SCSI upgrade I found in that huge lot I helped acquire.  It sits on the ROM slots, then you put in 2 512KE or Plus ROMs.

I have been playing with this off and on for the past year or so with little success.  It would always corrupt the drive after booting the first time.

I seriously have no idea why it works now.  It could be related to termination.  I did put a battery in.  It's tapping off the mains (I simply soldered a power cable.)  Perhaps it was getting corrupted because of a drop in power?  No idea.

In any event, this is probably the fastest you'll ever see a 512K boot.

Check this out! :lol:

https://youtu.be/Wg4-VJoQe5w

 

[Elfen]

I used to have a couple of those with a Dove add-on memory board. Loved them!

Sounds like you had corroded pins on the SCSI/ROM chips that loosened up over time with you fiddling with it. Glad it works! Congrats.

 

[olePigeon]

Perhaps the sockets were rusty.  I actually replaced the pins because a few them were broken off.

 

[CC_333]

This is neat!

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