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DIY Mac Plus ROM Chips (Giveaway)

Posted by: Stephen on 2021-01-03 13:32:46

I recently posted a tutorial which covers how to make replacement ROMsI recently posted a tutorial which covers how to make replacement ROMs for the Mac Plus. It's directly applicable to earlier compacts, such as the 128k and 512k. The process is similar for the Macintosh Classic & Classic II (different chips).

If anyone missed it, I'm offering 3 free sets of ROMs for anyone interested with two still remaining — just pay shipping. One set has already been claimed by @Mighty Jabba so don't miss out!

Posted by: Stephen on 2021-01-03 14:54:14

Another set has been claimed - now is your last chance to get a set for free!

Posted by: Stephen on 2021-01-04 09:06:58

The last set has been claimed! Remember, the tutorial is there if you want to make your own set and I'm here if you have any questions. Feel free to reach out —

Posted by: Mighty Jabba on 2021-01-08 17:24:01

Thanks again to Stephen for sending me a set of replacement ROMs (completely free!). I have 7 compact Macs of various types, but one of them has never worked since I received it -- a Mac Plus. I was able to confirm that the ROMs were the culprit a while back by swapping in some known good chips, so when Stephen's chips arrived all I had to do was pop them in and it booted right up! It's a super easy fix in that sense, but for a long time it wasn't obvious to me that the ROMs were at fault, and getting replacements is also generally not simple. But I'm hoping the guide Stephen posted will help others.

Posted by: Stephen on 2021-01-08 17:48:44

Thanks again to Stephen for sending me a set of replacement ROMs (completely free!). I have 7 compact Macs of various types, but one of them has never worked since I received it -- a Mac Plus. I was able to confirm that the ROMs were the culprit a while back by swapping in some known good chips, so when Stephen's chips arrived all I had to do was pop them in and it booted right up! It's a super easy fix in that sense, but for a long time it wasn't obvious to me that the ROMs were at fault, and getting replacements is also generally not simple. But I'm hoping the guide Stephen posted will help others.

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Woohoo! Happy to hear your Mac Plus has a new lease on life 🙂

I'm considering extended the give away to an additional three sets of ROMs. If anyone would be interested let me know in this thread and I'll see if there's more demand.

Posted by: chrisdaun on 2023-09-20 14:59:32

Woohoo! Happy to hear your Mac Plus has a new lease on life 🙂

I'm considering extended the give away to an additional three sets of ROMs. If anyone would be interested let me know in this thread and I'll see if there's more demand.

Super old thread but I need a set if you still have them 🙂

Posted by: DCB on 2024-02-22 11:34:08

I too am looking for a set of Mac Plus ROMs and would be happy to pay something for a known working set. I'm trying to update a friends 512K to a 512Ke for hard drive via Floppy port support.

Thanks,
David

Posted by: eharmon on 2024-02-23 14:30:39

Another option would be getting a ROM-inator Resurrections, which makes the Plus compatible with bigger standard EEPROMs:

ROM-inator Resurrections | infinityproducts

Mac ROM-inator I kit for Mac Plus, Mac 512K / 128K Standard Kit: 36USD(All necessary parts are included, only tools are required)Luxury Kit: 54USD( Standared kit and 2 sets of ROM)Feb 27th 2024: Some of the PCB designs have been updated.-Made the MacPlus and Mac512K (128K) selectors with solder...

en.infinityproducts.co.jp

Posted by: DCB on 2024-02-26 13:47:31

Update:
1) I ordered a XGecu T48 from Amazon (Where the seller was XGecu). This was slightly less likely to be a knock-off and supports slightly higher voltages needed for new chips.
2) I ordered a few AT27C512R-70PU EPROMs (from DigiKey).
3) Many thanks to Stephen for his Github posting of already split Mac Plus ROMs. !!!
4) Flashed successfully and installed in an original 512K today (Would not have be possible w/o this online help)

Might suggest one or two updates to the Instructable document but over all a great success!

Thanks again for the original work and documentation,
David

Posted by: trag on 2024-02-26 20:40:36

Might suggest one or two updates to the Instructable document but over all a great success!

It's a great article. But...

My main quibble and it's pretty much a nitpick is that it sort of implies that an XGecu programmer is required for the process. On the other hand, the instructions are for someone using an XGecu.

But the same procedure can be done with other programmers and I imagine that folks who already own a different programmer also already know that, so I can't really see the harm in the that aspect of hte article.