A89: Re: FYI: added info to J89hw.txt


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A89: Re: FYI: added info to J89hw.txt




cool documentation!
a question about the following code:

 Trap_11
 lea $1C5EA4,a0   ; Pointer to scratch word variable "+ $1C0000"
 bclr #1,$600015   ; Disable OSC2 (otherwise the LCD might interfere
                              ;  by doing RAM accesses in between!)
 nop                       ; Execute three NOPs to make SURE it's actually
 nop                       ;  three read accesses from within $21xxxx
 nop
 move.w #$2700,sr ; "make sure nobody's trying to do stupid things"
 move.w d0,(a0)     ; Do the $1Cxxxx write (any value in D0 will do)

 nop   ; And do it all again, just to be sure!
 nop
 nop
 move.w #$2700,sr
 move.w d0,(a0)
 bset #1,$600015 ; Finally reenable OSC2
 ;...
 ;trap #11 handler continues here
 ;...

where are the three reads from 20xxxx or 21xxxx that should be done just
before
move.w d0,(a0)   ?

Jeremie Knusel

----- Original Message -----
From: "Johan" <johei804@student.liu.se>
To: <assembly-89@lists.ticalc.org>
Sent: Monday, August 07, 2000 4:45 PM
Subject: A89: FYI: added info to J89hw.txt


>
> ...just wanted to mention that I've added misc stuff, including the
missing
> "protection" info, to http://m101.ryd.student.liu.se/J89hw.txt
> Nothing fancy, just for completeness. You probably know most of it
already.
>
>
> /Johan  "100 bytes is enough."
>




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