Re: 2 IIgs questions - please help

[dempson@actrix.gen.nz (David Empson)]

<macierno@cvm.msstate.edu> wrote:

> first - can I add a z80 card to the IIGS or will they only work with the
> IIe (or +)

It depends which card you have.  Most Z80 cards use the Inhibit signal
and take over the main memory of the machine.  This signal has a serious
limit on the IIgs: it only works if the system is set to SLOW speed in
the control panel.  Changing this setting may be sufficient to get some
cards working, but I'd still expect problems.

If the Z80 card contains its own RAM then it is more likely to work in
the IIgs.

I know that the Microsoft Softcard falls into the first category, and I
seem to recall that an Applied Engineering card did work with the IIgs.

Someone else may be able to provide more specific details.

> second - I want to add a hard drive and perhapps a cd-rom  - can i just
> purchase a SCSI interface and plug and play

In theory.  The main requirement is that you get a SCSI card which is
compatible with your hard drive and CD-ROM drive.

The major SCSI cards available for the Apple II are as follows (in
slowest to fastest order):

- (Original) Apple SCSI Card
- Apple High-Speed SCSI Card
- RamFast SCSI Card (revision D recommended for the IIgs)

All of these support hard drives and CD-ROM drives, though you need the
latest (revision C) firmware in the original Apple SCSI card if you want
to use a CD-ROM drive.

There are other SCSI cards around, but they are less likely to work with
a CD-ROM drive.

All of these cards use a Mac-compatible DB-25 connector, so you can use
the same "SCSI system cable" as would be used on a Mac.

Several other issues come to mind:

1. There isn't much point trying to use a modern multi-gigabyte SCSI
drive on an Apple II - you will have difficultly filling it up, and may
have trouble partitioning a drive larger than 1GB.

2. Some recent and semi-recent SCSI hard drives are incompatible with
the RamFast card (due to the drive requiring a SCSI feature which isn't
implemented by this card).  This includes at least one Quantum Fireball
model (around 500 MB) and some IBM models.  Getting an older drive would
be a safer bet with this card.

3. If you want to play audio CDs in the CD-ROM drive under software
control, you have more options with a RamFast card.  If you get an Apple
card, you will need one of Apple's oldest CD-ROM drive models: CD-SC,
CD-SC Plus or CD-150 (all of which are 1x).  The Apple cards don't
support audio commands with any third-party drives or with the Apple
CD-300 or later models.

4. Some older third-party CD-ROM drives don't work at all with the Apple
SCSI cards (from personal experience).  I haven't tried the same drive
with a RamFast, so I don't know how much better it is at dealing with
oddball mechanisms.

5. If you get an older RamFast, you may need to upgrade the firmware.  I
don't have any information on what is regarded as a "good" version, but
I'm sure someone else could help.

6. You might run into problems with termination and/or supply of
termination power.  The original Apple SCSI card is not terminated (you
need a pass-through terminator between it and the first device if you
are connecting two or more devices), and neither Apple SCSI card
supplies termination power unless a modification has been made (factory
fitted with late model High-Speed cards).  I never modified my cards - I
always ensured that my main hard drive supplied termination power
itself.


If you can avoid the CD-ROM drive, you might find that a Focus card from
Alltech Electronics is a better option than a SCSI card with external
hard drive.  (The Focus is an IDE controller with the drive mounted
directly on the card.)

> Ans if it is easy are there any places other than e-bay to get one??

None of the SCSI cards are being sold new any more.  Alltech Electronics
might have some.  Sun Remarketing is also a possibility for the Apple
cards, though they would probably charge too much.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P O Box 27-103, Wellington, New Zealand