The Mac ROM-inator II is back in stock – get yours now at the BMOW Store. The ROM-inator II is a replacement ROM SIMM for Macintosh II series computers and the Mac SE/30, adding a bootable ROM disk, 32-bit cleanliness, HD20 hard disk support, and more. Read more about it at the project’s home page. This is the 1.27 mm (0.05 inch) custom SIMM thickness that works best in finicky SIMM slots like those found on the SE/30.

 
Policies and Partnerships

The Macintosh ROM SIMM landscape has changed significantly since I started selling them in 2016. At that time, BMOW was the only vendor making and selling custom Mac ROM SIMMs, and the “product” was a combination of hardware and software. The hardware was the SIMM PCB and flash memory chips, while the software was a unique base ROM implementing on-the-fly decompression of a ROM disk image, auto-detection of the memory configuration, a new startup chime, and more. Sales of the hardware subsidized my development work on the base ROM software.

In the last few years, several other vendors have begun selling Mac ROM SIMMs too. Friendly competition is great, but it creates a potential dilemma for me if someone buys another vendor’s ROM SIMM and reprograms it with BMOW’s base ROM in order to get the on-the-fly ROM disk decompression and other features. It could turn into a situation where my base ROM software is subsidizing another competing product. To compound the problem, I didn’t have any clear usage policy or “license” for the base ROM to say whether this type of use was OK. Furthermore my FC8 compression algorithm is free open-source, but the BMOW base ROM which incorporates it is not. This all created a large gray area.

I hope to clarify this now by making the BMOW base ROM image explicitly free for personal use with anybody’s own Mac ROM SIMM, no matter what vendor they purchased it from. This is the simplest and best way of resolving the ambiguity for the benefit of the classic Mac community. I only ask that you don’t resdistribute the base ROM image elsewhere – come back to the BMOW Mac ROM-inator II details page if you need to download the image.

For vendors who might be interested in selling a version of their Mac ROM SIMM that’s pre-programmed with the BMOW base ROM software, I’m happy to partner with you. Please contact me to discuss it. CayMac Vintage and BMOW have recently partnered to bring the BMOW base ROM to their Mac ROM SIMM hardware, which you can check out here. Exciting stuff, and I’m glad to see new energy in this space that will benefit the classic Mac community at large.

The current state of custom Mac ROM SIMM technology is the result of hard work by many people stretching back 20 years: Gamba, Jeff Walther (trag), Doug Brown (dougg3), Rob Braun, myself, and many others. I wish you exciting ROM adventures, friends!