Alysis Systems Cache Switch INIT on Quadra
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The Alysis Compatibility INIT 2.2 automatically toggles the cache on the
Quadra 700 and 900, on-the-fly without having to restart. It also toggles
the cache between compatible and non-compatible applications while you are
multi-tasking. Unlike earlier versions, version 2.2 will also recognize
non-compatible Apple Menu Items (DAs). Users may add names of programs
they find to be incompatible with the Quadra or delete them as they become
compatible. Businesses and resellers are required to contact Alysis
Software for licensing and distribution rights.
On AppleLink, you can find contact information for the various vendors by
clicking the Library Index button to view the folder structure in the Tech
Info Library. An alphabetic listing of vendors is in the Third Party
Company Directory folder.
Apple's Internal Cache Switch on Quadra
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Don't change the caches on or off without restarting a Quadra 700, or you
may encounter LocalTalk network problems. When the Quadra 700 starts, the
system determines its effective processor speed (this has nothing to do
with the 68040's clock speed, and everything to do with the mode of the
processor's caches), and sets certain internal timings according to this
effective processor speed.
Two of the more important timings are for the floppy disk drive and
LocalTalk. Therefore, when the Quadra 700's caches are switched without
restarting, the timings set at startup are no longer valid, and the floppy
disk drive and LocalTalk won't work (or won't work properly). We monitored
a Quadra 700 after switching the caches on the fly. It transmitted an
inordinate amount of fragmented packets and never successfully registered
itself on the network, or registered and never located network services.
The Quadra 900 features the Peripheral Interface Controllers (PIC chips)
of the Macintosh IIfx. These I/O processors seem to work OK after having
the caches switched on/off on the fly, but we have a lot more testing to
do before we recommend this procedure.
Note the third-party cache switches routinely switch the caches on or off
on the fly, whereas the cache switch Apple distributes on the Tidbits disk
will only turn on or off the caches immediately if you hold down the option
key when changing the cache setting.