Want to add new features to your old Mac? The Mac ROM-inator II replaces the stock Macintosh ROM with a programmable flash memory module. Add a bootable ROM disk, change the startup chime, hack the icons, gain HD20 support and get a 32-bit clean ROM. The Mac ROM-inator supports the Macintosh IIx, IIcx, IIci, IIfx, IIsi, and SE/30.
Optional accessories for your Mac ROM-inator II:
The Mac ROM-inator II is great for breathing new life into your old II-series Mac or SE/30. Customized startup sounds and icons add a touch of fun, and the ROM disk provides fast and convenient boot-ups. The flash ROM comes pre-programmed with a custom ROM image with the following changes as defaults:
- Customized startup chime – major 9th arpeggio
- ROM disk image provides a diskless booting option
- New startup menu screen displays installed RAM, addressing mode, and ROM disk details
- Built-in HD20 disk support
- 32-bit clean
- Memory test is disabled for faster booting
- Happy Mac icon is replaced by a color smiling “pirate” Mac
The ROM-inator II is based on Doug Brown’s original Mac ROM SIMM design, used with permission. A portion of sales goes back to Doug.
ROM SIMM programmer utility software: Windows, Old Windows version, Mac OSX
FC8 compression command-line tool: Windows, Mac OSX
ROM-inator II 512K base ROM: baserom.rom
ROM disk image (uncompressed): romdisk.dsk
Default pre-programmed ROM-inator II contents: 4MB-fc3.rom
ROM disk driver source code: romdrv1.2.sit
The pre-programmed ROM image is compatible with the Macintosh IIx, IIcx, IIci, IIfx, IIsi, and SE/30. The Mac ROM-inator II module is physically compatible with any Macintosh having a 64-pin ROM SIMM socket, except the Quadra 660AV and 880AV. This includes the previously mentioned models as well as many other Quadra, LC, and Performa models. For these other models, the flash memory will need to be reprogrammed with an appropriate ROM image.
Some SE/30 hardware may require a SIMM shim to ensure ideal fit – see instructions for details. SE/30 computers running Mac OS System 7.5 or later require a software patch.
For a similar ROM upgrade for the Macintosh Plus, 512Ke, 512K, and 128K, see the original Mac ROM-inator Kit.
HD20 Support and 32-Bit Clean ROM
A nice benefit of the pre-programmed ROM image is to add built-in support for HD20-type hard disks, such as the HD20 hard disk emulation mode of the BMOW Floppy Emu. The Macintosh IIx, IIcx, IIfx, and SE/30 lack HD20 support in their stock ROMs, so this replacement ROM enables those machines to use HD20 disks.
The pre-programmed ROM image also makes the Mac 32-bit clean, enabling it to use more than 8MB of RAM natively without the need for special system enablers or extensions. Some older Macintosh models like the IIx, IIcx, and SE/30 have stock ROMs that are “dirty”, meaning they can’t support 32-bit addressing without ROM patches. Using the Mac ROM-inator II and the pre-programmed ROM image, the Mac SE/30 can support up to 128MB of RAM!
The built-in ROM disk is a 5.5MB bootable disk image containing System 7.1 and a collection of classic games. Using the ROM disk, it’s possible to create a diskless workstation without any physical disks attached. Once booted from the ROM disk, Appletalk file servers can also be mounted over a local network.
The ROM disk image is stored compressed in the module’s flash memory, and is decompressed on the fly as needed, in order to squeeze the largest possible disk image into the available space. This requires 1MB of RAM for caching of decompressed disk sectors, so a minimum of 2MB total system RAM is required. The ROM disk can be mounted as read-only, or as a read-write RAM disk.
When first powered on, the Macintosh will play a customized startup sound, and display diagnostic info about the amount of installed RAM, the current addressing mode, and the detected ROM disk type. After a moment, a startup menu will be displayed. To boot from the ROM disk as a read-only disk, press the R key on the keyboard. Or to convert the ROM disk into a writable RAM disk, press the A key. If no keys are pressed after five seconds, the Macintosh will boot normally from an attached SCSI disk, or wait for a floppy disk to be inserted.
If booting from a SCSI disk, any 32-bit enablers or extensions such as MODE32 or 32-Bit System Enabler must be removed from the system folder.
The Mac ROM-inator II’s flash memory can be reprogrammed using the ROM SIMM programmer, providing the ultimate in customization. There’s 4MB of flash memory available for any purpose, like a custom ROM disk image, alternate ROM code, digitized sounds, user interface tweaks, or other crazy experiments. Using compression, this is enough for the base 512K ROM image plus a roughly 5.5MB uncompressed disk image. Or fill the whole space with a collection of different base ROMs, selected from a startup menu. Go nuts!
The programmer is a USB peripheral, and connects to your PC with a standard USB B Mini cable (not included). The programmer utility software provides an easy GUI for updating the contents of the ROM SIMM’s flash memory. The utility program is compatible with Windows 7 or later, or Mac OSX, and you can also make it work on Linux if you compile the software for yourself. It’s based on Qt and should be easily portable.
The programmer board has an integrated on/off switch for convenience. Please connect the USB cable and insert the SIMM into the socket before switching the power on. Hot-plugging the ROM SIMM or the programmer itself may cause damage.
Creating a New ROM Disk
Don’t like the contents of the default ROM disk, and want to use your own? No problem. Create a bootable HFS disk image that’s 5.5MB (5767168 bytes) and fill it with whatever system software and other goodies you’d like. Then use the ROM SIMM Programmer to write a modified ROM and ROM disk to the Mac ROM-inator II SIMM. See the ROM disk creation tutorial for complete details.
Interested in alternative happy mac icons? Fancy a shot at reverse-engineering? How are your 68000 assembly skills? For true power users, all this and more is possible by patching the base ROM. Check out this ROM Hacking Tutorial for an example of modifying the startup sound behavior in the Mac’s base ROM code. Also see the linked threads and discussion at Rob Braun’s synack.net, which described the original ROM disk driver and related ROM hacks.
Get One Now
Check out the Mac ROM-inator II at the BMOW Store.35 comments