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34 lines
1.2 KiB
Markdown
34 lines
1.2 KiB
Markdown
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# DeskTop diassembly notes
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## DESKTOP.SYSTEM
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A short (8k) loader program. This is likely responsible for copying
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the rest to a RAM card (if available), then invoking the main app.
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## DESKTOP2.$F1
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This is large - 111k. It includes a loader, the DeskTop app (with both
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main memory and aux memory segments, filling everything from $4000 to
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$FFFF (except for I/O space and ProDOS), and still having more code -
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probably the disk copy code which is swapped in dynamically.
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The file is broken down into multiple segments:
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* segment 0: load - offset $0000, length $0580, loaded at $2000
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* segment 1: aux1 - offset $0580, length $8000, loaded at $4000 (through $BFFF)
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* segment 2: aux2 - offset $8580, length $1D00, loaded at $D000 (through $ECFF)
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* segment 3: aux2 - offset $A280, length $0500, loaded at $FB00 (through $FFFF)
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* segment 4: main - offset $A780, length $7F00, loaded at $4000 (through $BEFF)
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* main $BF00-$BFFF is ProDOS buffers
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* main $C000-$CFFF is I/O space
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* main $D000-$FFFF is ProDOS
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* segment 5: _TBD_ - 38k so must be further subdivided.
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Much of the space is data:
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* API jump table at $40E5, param details at $4184
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* Font is at $8800
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Icon bitmaps are at $FF00-ish (.SYSTEM file is $FF06), stride 5, $22x$11px
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