Mac 512k troubleshooting

[devang1944]

Hi all, new to the forum. I recently acquired a large hoard of old compact Macs, one of them being this 512k that I'm working on. It started off with a memory error, so I ordered some NOS chips online, and replaced those. The internal floppy needed some love, so I cleaned and re-lubed that.

Now, I'm at the point where it will start to boot from a 400k System 2.0 floppy. Now, however, I get the "Sorry, a system error occurred. ID=02" with the little bomb in the top left, accompanied by small dots in a line, going vertically through the first "r" of "Sorry". Any advice on how to proceed? I have reviewed "The Dead Mac Scrolls" to no avail. Picture attached.

Thank you in advance!

 

[devang1944]

Well, I ended up swapping out the ROM chips from a Mac Plus, and changed one more RAM chip, and it works! now the question is, where can I find more ROM chips, or maybe the original Rominator?

 

[Cam]

I went with a Rominator for my SE/30 reloaded since it provides a little more 'bang for the buck'.

BMOW has discontinued selling the 512k version (https://www.bigmessowires.com/mac-rom-inator/), but it looks like you can still order them from here https://en.infinityproducts.co.jp/product-page/rom-inator-resurrections.

Maybe someone else knows of another source?

 

[devang1944]

I went with a Rominator for my SE/30 reloaded since it provides a little more 'bang for the buck'.

BMOW has discontinued selling the 512k version (https://www.bigmessowires.com/mac-rom-inator/), but it looks like you can still order them from here https://en.infinityproducts.co.jp/product-page/rom-inator-resurrections.

Maybe someone else knows of another source?

Looks like those guys are out of stock. I'll have to keep an eye on it.

 

[Cam]

Looks like those guys are out of stock. I'll have to keep an eye on it.

Stuff being out of stock is pretty much par for the course with the chip shortage. I guess you could grab the gerber files and the rest from Big Mess O wires and build one from scratch.

 

[dochilli]

If you want to burn new ROMs, then you can use 27C256 or 27C512 Eproms:

Mac 512k error code 014120

Hi, I have recently been charged with repairing a Mac512k. On powering up i get a beep followed by the 'Sad Mac' and an error 014120 I think this is a ROM issue, is this correct? There is another site "http://members.tripod.com/elfen_magix/sadcodes.html" which suggests that this is...

forums.macrumors.com

 

[dochilli]

And an instruction for burning ROMs (mac plus):

Create Macintosh Plus ROMs

Create Macintosh Plus ROMs: This Instructable will guide you through the process of "ripping" EPROM images from from your Macintosh Plus ROM chips and (or) "burning" the images to new chips. The process will basically be performed twice to create both "hi" and "lo" ROM chips f…

www.instructables.com

 

[Cam]

Burning your own is probably the cheapest way of getting the machine running, if you have access to the equipment.

 

[devang1944]

Appreciate the info! I was able to get into contact with someone, and have new ROMs on the way. For now, It's working happily with the ROMs from my Plus.