SCSI terminator power

[dn276@cleveland.Freenet.Edu (Norman L Jaojoco)]

I'm having problems with my set-up and I'm curious if it is due to
the lack of sufficient terminator power.

My SCSI chain is as follows:
Tulin Technologies Floptical	ID2
AppleCD SC+			ID3
Apple Tape Backup 40		ID1
Storage Dimensions Macinstor120	ID6

I am using an Apple IIgs ROM01 with RamFAST SCSI Rev.C ROM 3.01e.
I have the DIP SW #1 set to on to turn on terminator power.  I have
an Apple Active Terminator at the end of the chain.

The problem is that when I try to optimize my floptical disk with
ProSel-16 v8.84, it gets past the first part with the trees, but
shortly after displaying the time to wait (15 minutes) it draws a
yellow line about 2/3rds the way down and locks up.

As far as I can tell, none of the drives supply terminator power.
Can any of my SCSI devices be configured to supply terminator power?

What is the difference between passive and active termination?  Will
one work better than the other on the Apple IIgs?  (BTW, I opened
up my terminator and noticed a chip inside labeled TI-SCSI285N.)

I noticed that APS sells this $99 terminator that can be configured
to supply terminator power to the SCSI bus.  Has anyone tried this
out?  Do you think this will fix my problems?

One of the wierd things that I noticed is that I have to actually
shut down the GS and all the SCSI devices in order for the GS to
properly reset.  Seems to me that somehow, power is being fed back
into the GS from the SCSI chain.

I recently replaced my 16K cache on the my ZipGS 1.02 with 64K of
Sony 45ns .6" static RAM chips, I wonder if this has anything to
do with the problems?  (Since I did both upgrades at the same time,
ie. a floptical drive add-on along with 64K cache replacement. I
don't really know where exactly the problem is.)

What makes me think that it might be a SCSI problem is that I replaced
one of the 50-50 SCSI cables with a better (Apple brand) one, and
the ProSel-16 optimizer worked a little further than it did before.

Are Apple brand SCSI cables pretty good?  I know that they might not
be worth what they are being sold for, but given the fact they are priced
too high, are they at least made of decent quality?

The next thing that I will try is to optimize with the ZipGS turned
off.  I don't know what good it will do, but I'll try anything.

I was also thinking that with DIP SW#1 turned on (on RamFAST), my GS
power supply maybe over burdened.

For completeness, here is my GS setup:

Apple IIgs ROM 01 w/ 3MB RAM (CV Tech GS-Memory w/ 2MB & Apple 1MB PB'd)
slots
 1	Thunderware Lightning ScanGS
 2	Sequential Systems RamFAST Rev.C ROM 3.01e
 3	Apple Video Overlay Card
 4	ZipGS v1.02 8/64
 5	Econ Technologies SoundMeister
 6	Apple SuperDrive controller w/ Apple SuperDrive
 7	Applied Engineering PC Transporter w/ Transdrive 5.25
ports
 ADB	IIgs keyboard & mouse
 RGB	AE colorswitch adapter (PC/T) to Apple RGB monitor
 drive	Apple 3.5 to Apple 5.25
 game	CH Products Mach III
 pr
printer	LocalTalk
 modem	Digicom Eagle+ 14.4

-- 
Norman LJ