APPENDIX TWO



54016-54271 | PIA                                 636-639 PTRIG#          |
            |                                     632-635 STICK#          |
53760-54015 | POKEY                               624-631 PADDL#          |
            |                                     562     SSKCTL          |
            |                                     16      POKMSK          |
53504-53759 | unused                                                      |
53248-53503 | GTIA or CTIA                        704-707 PCOLR#          |
            |                                     708-712 COLOR#          |
            |                                     644-647 STRIG#          |
            |                                     623 GPRIOR              |
            |                                                             |
            |                                                             |
53247 _____ | Unused 4K ROM block _______________________________________ |
            |                                                             |
            |                                                             |
49151 _____ | 8K BASIC ROM                                                |
            | or Left cartridge (A)                                       |
            |                                                             |
            |                                                             |
40959 _____ | Top of BASIC RAM or                 106     RAMTOP          |
____________|_____________________________________________________________|
            |                                     740     RAMSIZ          |
            |                                                             |
            | Right cartridge (B) ROM if present                          |
            | (Atari 800 only)                                            |
            |                                                             |
            |                                                             |
Size and    |                                                             |
location    |                                                             |
vary with   |                                                             |
GRAPHICS    |                                                             |
mode        |                                                             |
            | Text window screen RAM              60,661 TXTMSC           |
            | 40800 for GR.0                                              |
            |                                                             |
            | Bottom of screen RAM                88,89   SAVMSC          |
            | 40000 for GR.0                                              |
            |                                                             |
            | Display List:                       560,561 SDLSTL          |
            | 39968 for GR.0                                              |
            |                                                             |
            | Top of BASIC RAM                    741,742 MEMTOP          |
(OS)        |                                                             |
            |                                                             |
            |                                                             |