Re: Help w/ these GS cards

[toddpw@mince.ugcs.caltech.edu (Todd P. Whitesel)]

dempson@atlantis.actrix.gen.nz (David Empson) writes:

>> 1) Zip/GS 1.01 He was told this was flakey. Is this true? should I attempt
>> to use it?

>I don't know about any rumoured problems with the card, but I've never
>actively investigated it, so there may well be problems.  Version 1.02
>came out very quickly after the ZIP was released, and was still the
>current version (with a wide range of different options on the card
>enabled) when I last saw a new one.

1.01 _was_ flaky. I hope ZIP is still around to upgrade it. I don't remember
what the problems were, but ZIP was very eager to upgrade everyone's cards
back then so I'd imagine the bugs were fairly embarrassing when they hit...

>1-3   AppleTalk Delay.  This switch should be set ON unless you are
>      booting from an AppleShare server, or using AppleTalk with
>      System 5.0.4 or earlier.

Actually this is propaganda. With beefier ZIPs it does not prevent packet
loss problems. The correct solution is either to run ZipTalk (system 5) or
to use system 6. When booting from an appleshare server, it is better to
boot the IIgs with the ZIP disabled and have the ZIP.INIT enable it after
system 6 or the ZipTalk init have been loaded.

The AppleTalk Delay is also a significant performance drain. When VBL
interrupts are active (e.g. any desktop program), AppleTalk Delay will
kick in every 16.6 ms and turn your ZIP off for 5 ms, nearly 1/3 of the
time. This is yucky.

>1-5   CPS Follow.  This switch must be set OFF.  It causes the ZIP
>      to be disabled automatically when the IIgs switches to "Normal"
>      speed.  This is a requirement for a reasonable amount of timing-
>      critical software.

I don't recommend anybody _ever_ setting this to on. You really don't gain
much and it screws up floppy drives. It will also defeat the system 6 fix
for the AppleTalk problem, if I remember right (I'm not 100% sure).

Todd Whitesel
toddpw @ ugcs.caltech.edu