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Re: AUX memory question
In article <3AA49C4F.CD67094D@swbell.net>,
Rubywand <rubywand@swbell.net> wrote:
>Dennis Jenkins writes ...
>>
> ....
>
>
>ref. David Empson wrote ....
>>>
>
>Have you seen a complete diagram of the 128K IIe memory map? It
>certainly helps when trying to understand all this. Here is a rough
>version (not to scale vertically).
Nice memory map! It inspired me to draw a similar map
explaining the memory usare of SoftCard CP/M:
Apple II Softcard CP/M memory usage
0100H Z-80 address
$0100 6502 address
44K CP/M: does not use Language Card
56K CP/M: uses Language Card, bank 2 only (TPA)
60K CP/M: uses Language Card: bank 2 for TPA, bank 1 for parts of BDOS+BIOS
Note that the Apple II hi-res graphics screens are situated right in
the middle of the Softcard CP/M TPA. Hi-res graphics programming on
SoftCard CP/M therefore requires special precautions. Microsoft
GBASIC solves this by reserving an 8K large memory area, right in the
middle of the Basic interpreter, for hi-res graphics.
Z80 addr 6502 addr
______________ ______________
0000H |CP/M zero page| $1000 | |
|______________| | |
0100H |CP/M TPA start| | |
| | | |
| | | |
| | | |
| | | |
|______________| |______________|
1000H | | $2000 | |
| | | |
| | | Aux Hi-res |
| CP/M TPA | | |
| | | page 1X |
| | | |
| | | |
|______________| |______________|
3000H | | $4000 | |
| | | |
| | | Aux Hi-res |
| CP/M TPA | | |
| | | page 2X |
| | | |
| | | |
|______________| |______________|
5000H | | $6000 | |
| | | |
| CP/M TPA | | |
| | | |
| | | |
| | | |
... ...
| | | |
| | | |
| | | |
| | | |
| | | |
|______________| | |
9400H | 44K BDOS | $A400 | |
| starts here | | |
| | | |
| | | |
| CP/M 56/60K | | |
| TPA | | |
| | | |
| | | |
| | | |
| 44K BIOS end | | |
AFFFH |______________| $BFFF |______________| ______________
B000H | | $D000 | || | | |
| | | LC || LC | | |
| | |bank 1||bank 2| | |
| CP/M 56/60K | | || | | |
| TPA | | 60K || Used | | |
| | | BDOS+|| by | | |
| | | BIOS || CP/M | | Applesoft |
| | |______||______| | |
C000H | | $E000 | | | BASIC |
| | | | | |
|______________| | | | ROM |
C400H | 56K BDOS | $E400 | | | |
| starts here | | | | |
| | | Language | | |
| | | | | |
| | | Card | | |
| | | | | |
|______________| | | | |
D400H | 60K BDOS | $F400 | | | |
| starts here | | | |..............|
D800H | | $F800 | | | Monitor |
| 56K BIOS end | | | | ROM |
|______________| |______________| |______________|
DFFAH | 6502 vectors | $FFFA | 6502 vectors | | 6502 vectors |
DFFFH |______________| $FFFF |______________| |______________|
_____________
E000H $C000 | Motherboard |
| I/O |
|_____________|
E090H $C090 | Slot I/O |
| (DEVSEL) |
|_____________|
E100H $C100 | |
| Slot CX ROM |
| (IOSEL) |
| |
|_____________|
E300H $C300 | Slot C3 ROM |
| (IOSEL) |
|_____________|
E400H $C400 | |
| |
| Slot CX ROM |
| (IOSEL) |
| |
| |
| |
|_____________|
E800H $C800 | |
| Slot ROM |
| (IOSTROBE) |
| |
| shared |
| between |
| slots |
EFFFH $CFFF |_____________|
______________ ______________
F000H | Unused by Z80| $0000 |6502 zero page|
|______________| |______________|
F100H | Unused by Z80| $0100 | 6502 stack |
|______________| |______________|
F200H | I/O cfg blk | $0200 | Keybd buff |
| Device driv | |______________|
F300H | Patch area | $0300 | Page 3 |
|______________| |______________|
F400H | | | |
| | | |
| Text/lores GR| | Text/lores GR|
| | | |
| | | page 1 |
| | | |
| | | |
|______________| |______________|
F800H | | $0800 | |
| | | Text/lores GR|
| CP/M | | |
| | | page 2 |
| RWTS | |______________|
FC00H | | $0C00 | |
| | | |
| | | |
FFFFH |______________| $0FFF |______________|
--
----------------------------------------------------------------
Paul Schlyter, Swedish Amateur Astronomer's Society (SAAF)
Grev Turegatan 40, S-114 38 Stockholm, SWEDEN
e-mail: pausch at saaf dot se or paul.schlyter at ausys dot se
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