DOSIUS wrote:5-6MB. You could only use 7MB on the IIgs, (was it 7MB on the 1, 6MB on the 3?)...something like
that. Maybe a ROM 0 or 1 would be better depending on the situation?

ROM 01 had 256K of RAM on the motherboard (128K of "slow" RAM [//e emulation]) and could have 8.25 megs (an additional 8 megs); the ROM 03 had 1.1 megs on the motherboard (1 meg of "fast" RAM, 128K of "slow" RAM). However, there was a problem that limited DMA to only the first four megs in the memory expansion slot. Not normally a problem but sometimes.... I have a ROM 03 with 7 megs in the expansion slot, and a ROM 01 with 6 megs in the expansion slot. It all works fine, with my equipment, but some SCSI cards don't like it.

For a project like this, a ROM 03 would be great - no need to use any of the expansion slots, unless you really wanted to.

Exegete AKA Roy Miller
Faith Orthodox Presbyterian Church
Apple ][ forever!

Say WHAT?

The Apple ][ disc drivers were the absolute worst.
And here's why:

1 - use of non-standard encoding (group, not FM). This
was done so the 6502 could do the decoding WITHOUT a
controller. Saves a couple of bucks, but the 6502 isn't
actually FAST enough.

so...

2 - the drives were hyper-critical on motor speed.
They had to be matched or tuned...

and...

3 - there is no media compatibility.

This design works for a home machine (I guess), but for
anything else, it fundamentally blows chunks.

Just my humble (but correct) opinion.
Ratboy666.

Well, old Apple was ok, but new Apple sucks. I wrote the spec for my OS, if anyone wants a copy just give me an email, and ill send you a copy. And MOS technologies rules(err ruled)!!