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Re: AUX memory question



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).

         MAIN RAM         AUX RAM            I/O             ROM

      ______________   ______________
0000 |Main zero page| |Aux zero page |
     |______________| |______________|
0100 |  Main stack  | |  Aux stack   |
     |______________| |______________|
0200 |              | |              |
     |              | |              |
0300 |              | |              |
     |______________| |______________|
0400 |              | |              |
     |              | |              |
     | Main text/GR | |  Aux text/GR |
     |              | |              |
     |    page 1    | |    page 1X   |
     |              | |              |
     |              | |              |
     |______________| |______________|
0800 |              | |              |
     |              | |              |
     | Main text/GR | |  Aux text/GR |
     |              | |              |
     |    page 2    | |    page 2X   |
     |              | |              |
     |              | |              |
     |______________| |______________|
0C00 |              | |              |
     |              | |              |
           ...              ...
     |              | |              |
     |______________| |______________|
2000 |              | |              |
     |              | |              |
     | Main Hi-res  | |  Aux Hi-res  |
     |              | |              |
     |    page 1    | |    page 1X   |
     |              | |              |
     |              | |              |
     |______________| |______________|
4000 |              | |              |
     |              | |              |
     | Main Hi-res  | |  Aux Hi-res  |
     |              | |              |
     |    page 2    | |    page 2X   |
     |              | |              |
     |              | |              |
     |______________| |______________|
6000 |              | |              |
     |              | |              |
     |              | |              |
           ...              ...
     |              | |              |
     |              | |              |
BFFF |______________| |______________|  _____________ 
C000                                   | Motherboard |
                                       |     I/O     |
                                       |_____________|
C090                                   |  Slot I/O   |
                                       |  (DEVSEL)   |
                                       |_____________|  _____________ 
C100                                   |             | |             |
                                       | Slot CX ROM | |  Int CX ROM |
                                       |   (IOSEL)   | |             |
                                       |             | |             |
                                       |_____________| |_____________|
C300                                   | Slot C3 ROM | |  Int C3 ROM |
                                       |   (IOSEL)   | |             |
                                       |_____________| |_____________|
C400                                   |             | |             |
                                       |             | |             |
                                       | Slot CX ROM | |  Int CX ROM |
                                       |   (IOSEL)   | |             |
                                       |             | |             |
                                       |             | |             |
                                       |             | |             |
                                       |_____________| |_____________|
C800                                   |             | |             |
                                       |   Slot ROM  | |             |
                                       |  (IOSTROBE) | |  Int C3 ROM |
                                       |             | |             |
                                       |    shared   | |             |
                                       |   between   | |             |
                                       |    slots    | |             |
CFFF  ______  ______   ______  ______  |_____________| |_____________|
D000 |      ||      | |      ||      |                 |             |
     | Main || Main | |  Aux ||  Aux |                 |             |
     |      ||      | |      ||      |                 |             |
     |  LC  ||  LC  | |  LC  ||  LC  |                 |             |
     |      ||      | |      ||      |                 |             |
     | bank || bank | | bank || bank |                 |             |
     |   1  ||   2  | |   1  ||   2  |                 |  Applesoft  |
     |______||______| |______||______|                 |             |
E000 |              | |              |                 |    BASIC    |
     |              | |              |                 |             |
     |              | |              |                 |     ROM     |
     |              | |              |                 |             |
     |              | |              |                 |             |
     |     Main     | |      Aux     |                 |             |
     |              | |              |                 |             |
     |   Language   | |   Language   |                 |             |
     |              | |              |                 |             |
     |     Card     | |     Card     |                 |             |
     |              | |              |                 |             |
     |              | |              |                 |.............|
F800 |              | |              |                 |   Monitor   |
     |              | |              |                 |             |
     |              | |              |                 |     ROM     |
FFFF |______________| |______________|                 |_____________|

<<



> (rubywand, I suggest putting this excellent memory map into the FAQ)
> 
 ....

     Good idea. The map plus David's related softswitch info will make a juicy
addition.



Rubywand