Re: Upgrading the ROM on a IIGS

[Rubywand <rubywand@swbell.net>]

Tail Kinker writes ...
> 
> I have a ROM version 1, and from what I've heard, that's
> worthless...

     ??? If required to use just one IIgs and given a choice of a ROM-01 or ROM
3, my choice would be the ROM-01-- there would not even be any hesitation.

     The main reason for choosing the ROM-01 is compatibility with pre-System 5
software (which includes most commercial IIgs software). If you want to play
some "ProDOS 16" game, you just pop in the diskette and play it-- no hunting
around for a 'fixed' version. The same goes for all sorts of early utlities and
other kinds of software.

     Is the ROM 3 a better machine? Yes, it is. On the other hand, once you add
the motherboard Slot jumpers to improve +5V and +12V power distribution, the
ROM 3's quieter bus advantage disappears. (In fact, ROM 3 users who pile in
Slot cards should probably add the jumpers, too.)

     8MB Expansion Memory cards have pretty well equalized things on the memory
front; and, the base system speed advantage is so small as to be barely
noticable.



> Is it at all possible to upgrade the ROM, and if so,
> what's the best procedure?

     As has been noted, the ROM-01 IIgs can not be upgraded to a ROM 3. You can
modify the ROM code-- e.g. change what happens right after a Reset, etc.-- by
writing a new PROM. You would probably not want to make any changes which make
your GS incompatible with GS System.




Rubywand