[comp.sys.apple] IIgs slot 4 stuff

AWCTTYPA@UIAMVS.BITNET ("David A. Lyons") (03/31/88)

>Date:         Wed, 23 Mar 88 22:22:05 GMT
>Reply-To:     Info-Apple@BRL.ARPA
>From:         Scott Kempf <geowhiz!scott@speedy.wisc.EDU>
>Subject:      Re: GS Slots
>
>>another thing: the mouse uses the Apple Desktop Port. Is ALL info from the
> mouse
>>coming from slot 4 anyway? or is this only in 8-bit mode?
>
>The mouse port is just for //e compatibility.  8-bit mode can use the Apple
>Desktop Bus.  //gs mouse programs should run with slot 4 set to "you card".
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Unfortunately, they currently don't.  (Well, they *run*...but the mouse is
frozen.)  While none of the I/O locations are in the slot 4 space ($C0C0..F),
the ROM space is still used ($C400..FF).  The event manager uses the routines
in the slot 4 ROM instead of having its own routines.  Oh...the screen holes
are used, too ($478+4, $4F8+4, ... $7F8+4).

Note that you CAN use another card in slot 4 while the mouse is switched in,
*if* your other card doesn't have ROM on it and your software doesn't touch
the screen holes.  For example, I use an Echo II in slot 4 with no trouble.

>______________________________________________________________________________
>Scott Kempf                         Blue itself teaches us blue.  -Bill Ranson
>MAIL:  1302 Rutledge St., Madison, WI  53703    PHONE:  (608) 255-6205  (home)
>UUCP:  {seismo, topaz, harvard, ihnp4}!uwvax!geowhiz!scott
>ARPA:  geowhiz!scott@spool.wisc.edu             PHONE:  (608) 262-6154  (work)
>BITNET: scott%geowhiz.uucp%spool.wisc.edu@wiscvm.bitnet

--David A. Lyons  a.k.a.  DAL Systems
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