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From: david@wraith.cs.uow.edu.au (David E A Wilson)
Newsgroups: comp.sys.apple2.programmer
Subject: Re: Hi-res Graphics
Date: 19 Oct 1993 08:17:06 +1000
Organization: University of Wollongong, NSW, Australia.
Lines: 61
Message-ID: <29v4l2$pv9@wraith.cs.uow.edu.au>
References: <29ner2$1ie@charm.magnus.acs.ohio-state.edu> <CF0toM.FrF@actrix.gen.nz> <29s4ot$dn6@crcnis1.unl.edu> <CF3E03.Gv2@actrix.gen.nz> <29uheu$jng@crcnis1.unl.edu>
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gberigan@cse.unl.edu (Greg Berigan) writes:
>But then that would imply that blocks 8 to 16 are mapped linearly to the
>DHGR aux page.  But then where does it toss the block pointer table to
>the file?

Use the source Luke :-)...

Apple II
Technical Notes
_____________________________________________________________________________
                                                  Developer Technical Support
ProDOS 8
#18:    /RAM Memory Map

Revised by:    Matt Deatherage                                  November 1988
Written by:    Pete McDonald                                    December 1986

This Technical Note describes the block to actual memory location mapping of 
/RAM.
_____________________________________________________________________________

                Blocks     Address Range
            ______________________________
           |   $70-$7F   |   $E000-$EFFF  |	<= Note error here $E000-$FFFF
           |   $68-$6F   |   $D000-$DFFF  |  (Bank 2)
           |   $60-$67   |   $D000-$DFFF  |  (Bank 1)
           |   $4E-$5C   |   $A200-$BFFF  |
           |   $3D-$4C   |   $8200-$A1FF  |
           |   $2C-$3B   |   $6200-$81FF  |
           |   $1B-$2A   |   $4200-$61FF  |	<= rest of DHres 2 file
           |   $0A-$19   |   $2200-$41FF  |	<= rest of DHres file + 1st
            ______________________________	   block of DHres 2 file
           |   $5D-$5F   |   $1A00-$1FFF  |
           |     $4D     |   $1800-$19FF  |
           |     $3C     |   $1600-$17FF  |
           |     $2B     |   $1400-$15FF  |
           |     $1A     |   $1200-$13FF  |	<= ptr blk for DHres 2 file
           |     $09     |   $1000-$11FF  |	<= pointer block for DHres file
           |     $08     |   $2000-$21FF  |	<= 1st block of DHres file
           |     $02     |   $0E00-$0FFF  |
           |     $03     |     Bitmap*    |
            ______________________________

Notes:
*     Synthesized.
1.    Blocks 0, 1, 4, 5, 6, and 7 do not exist.
2.    Block $7F contains the Reset, IRQ, and NMI vectors and is normally 
      marked as used.
3.    The memory from $0C00 - $0DFF is a general purpose buffer used by the 
      /RAM driver.

>I never had problems with using only 1 8K file.  I've never seen page 2x
>displayed, so never had reason to use it, although someone claimed it
>was possible.  Is this done in the same manner that allows FLASHing text
>in 80 columns?

No - you just have to turn 80STORE off and then select PAGE2 with double res
turned on.
-- 
David Wilson				+61 42 213802 voice, +61 42 213262 fax
Dept Comp Sci, Uni of Wollongong	david@cs.uow.edu.au

