Jet Set Willy Memory Usage
                       ==========================

 4000  +--------+      6000  +--------+      7000  +--------+
       | Screen |            |        |            |        |
       |  Top   |            |        |            |        |
       | Third  |            | Screen |            | Screen |
 4800  +--------+      6800  + Buffer +      7800  + Buffer +
       | Screen |            |   2    |            |   1    |
       | Middle |            |        |            |        |
       | Third  |            |        |            |        |
 5000  +--------+      7000  +--------+      8000  +--------+
       | Screen |
       | Bottom |
       | Third  |
 5800  +--------+      5C00  +--------+      5E00  +--------+
       | ATTRs  |            |        |            |        |
       |  Top   |            |        |            |        |
       | Third  |            |  ATTR  |            |  ATTR  |
 5900  +--------+      5D00  + Buffer +      5F00  + Buffer +
       | ATTRs  |            |   2    |            |   1    |
       | Middle |            |        |            |        |
       | Third  |            |        |            |        |
 5A00  +--------+      5E00  +--------+      6000  +--------+
       | ATTRs  |
       | Bottom |
       | Third  |
 5B00  +--------+
       | Stack  |
 5C00  +--------+

   8000 +-------------------+      9800 +-------------------+
        |    Room Buffer    |           | ATTRs for Startup |
   8100 +-------------------+      9900 +    Screen and     +
        |  Guardian Buffer  |           |  bottom third of  |
   8200 +-------------------+      9A00 +     Gameplay      +
        | Pixel-line lookup |           |      Screen       |
   8300 +-------------------+      9B00 +-------------------+
        |  Rope Structure   |           |  Number Sprites   |
   8400 +-------------------+      9B80 +-----(Room 91)-----+
        |   Startup Code    |           |ATTRs for passwords|
   8431 +-------------------+      9C00 +-------------------+
        |   Triangle Data   |           |      unused       |
   8454 +-------------------+      9C40 +-------------------+
        |       Text        |           |    Foot/Barrel    |
   85CB +-------------------+      9C80 +-------------------+
        |     Variables     |           |       Maria       |
   85E5 +-------------------+      9D00 +-------------------+
        | Teleport Password |           |       Willy       |
   85FB +-------------------+      9E00 +-------------------+
        | Moonlight Sonata  |           |  Password codes   |
   865F +-------------------+      9EB3 +-----(Room 94)-----+
        |     Rich Man      |           |      unused       |
   869F +-------------------+      9F00 +-------------------+
        |   Password Code   |           | unused (Room 95)  |
   87CA +-------------------+      A000 +-------------------+
        |                   |           |   Guardian Data   |
   8800 +                   +      A3FF +-------------------+
        |                   |           |   Object Table    |
   8C00 +                   +      A600 +-------------------+
        |    Game Engine    |           |      Toilet       |
   9000 +                   +      A680 +-------------------+
        |                   |           | Collection Table  |
   9400 +                   +      A700 +-------------------+
        |                   |           |   Rooms 103-106   |
   96F4 +-------------------+      AB00 +-------------------+
        |    Unused Code    |           |      Sprites      |
   9718 +-------------------+      C000 +-------------------+
        |  Spare (Room 87)  |           |    Rooms 0-63     |
   9800 +-------------------+      FFFF +-------------------+