The U36 ROM is for an empty socket that the engineers left in the C128 in case folks in the future ever wanted to enhance their machines with programmed ROMs. What a very cool and forward-thinking idea!
Naturally, a lot of people have created some very cool enhancements for that empty socket.
The three I currently have include:
- Super 81 Utilities
- GEOS 128 v2 w/ 1571
Super 81 Utilities
This is a very cool upgrade for anyone with 1581 drives attached to their system.
- It can copy whole disks from 1541 or 1571 format to 1581 partitions.
- Copy 1541 or 1571 files to 1581 disks.
- Copy 1581 files to 1571 disks.
- Backup 1581 disks or files with 1 or 2 1581s.
- 1581 Disk Editor, Drive Monitor & RAM Writer.
- Perform many CP/M and MS-DOS utility functions.
KeyDOS (Antigrav Toolkit)
This ROM has so many "pro" features, it's kind of ridiculous. If you don't believe me, check out its 54-page manual! And, it is compatible with pretty much everything under the sun.
How all of this fits into 32KB is amazing in its own right.
What's also cool about this ROM (and maybe all of these ROMs? But this one specifically explains how to do it in the manual) is that it can be installed in a Commodore REU expansion rather than the socket inside the machine. It would require a very minor mod to the PCB of the REU, but nothing super scary. Neat idea either way.
GEOS 128 v2 w/ 1571
This ROM allows for some of the GEOS boot code to be loaded from a ROM chip instead of off of a floppy. It doesn't really speed up the boot-up process that much, but it does speed things up quite a bit should you ever need to do a reboot, and other occasional processes. Obviously loading off a ROM is going to be faster than most disk reads - even compared to a 1571. However, my current setup boots off of a 1581 on Drive 9, so I'm not using this one anymore. They make a ROM for folks with 1581 drives, too - but only when set to drive 8. I can flip my drive to 8 no sweat, but it's not my preferred setup right now so I have just left things as-is.
I love my current setup so much, I plan on showing you all more about that soon.
There are several more ROMs that I'm aware of. They are:
- Basic 8 ROM
- File Browser v6
- Servant 128 (I think I owned this one once but lost it)
- Turbo Assembler