Re: "Co-Processor" Apple ?

[mjmahon@aol.com (Michael J. Mahon)]

Wayne Stewart replied:

>Michael J. Mahon wrote:
>
>> Can anyone give me a quick answer about how other accelerators,
>> both //e and IIgs, temporarily reduce speed?  (I would expect that
>> the IIgs accelerators track the $C036 register, but I have no idea
>> about the other //e accelerators.)
>
> From the TransWarp manual:
>
>Programmers can also control TransWarp from within their programs by
>writing a specific value to a certain memory location. This location,
>expressed in hexadecimal notation, is $C074, and in decimal notation,
>49268 (-16268 Integer BASIC complement). The valid values which can be
>written to this location are 0, 1, or 3. A zero enables the maximum
>hardware default speed. A one will cause the TransWarp card to run at
>1 MHz. Writing a three will disable the TransWarp card completely and
>pass processing control to the Apple’s processor until the TransWarp
>is again activated by cold-booting the system. The following example
>Applesoft BASIC program line will slow the TransWarp to the 1 MHz
>clock rate.
>
>]10 POKE 49268,1

Very interesting, Wayne.

Is there any information on how the TransWarp slows down
temporarily when accessing a 5.25" disk, for example?

I'm looking for things that _all_ accelerators had to support
to minimize the number of different approaches.
-michael

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