FFFF   Top of memory                  X
                                                X
                                                X 
          F000   ROM     MM52164    IC20        X

          E000   Reserved -Disk Operating System 
                                                X
                                                X
          D000   ROM     MM52132    IC21        X
                                                X
                                                X
          C000   ROM     MM52164    IC20        X
                                                X
          BC00   Empty                          X
          B800   VIA     6522       IC1         X
          B400   Extension          PL8         X
          B000   PPI     INS8255    IC25	  X
                                                X
                                                X 
          A000   ROM     MN52132    IC24        X
                                                X
          9800   Empty                          X
          9400   RAM     2114       ICs 32&33   X
          9000   RAM     2114       ICs 34&35   X
          8C00   RAM     2114       ICs 36&37   X
          8800   RAM     2114       ICs 38&39   X
          8400   RAM     2114       ICs 40&41   X
          8000   RAM     2114       ICs 42&43   X

          3C00   For RAM expansion off board
          3800   RAM     2114       ICs 18&19   X
          3400   RAM     2114       ICs 16&17   X
          3000   RAM     2114       ICs 14&15   X
          2C00   RAM     2114       ICs 12&13   X
          2800   RAM     2114       ICs 10&ll   X

          0400   Reserved for Eurocards
          0000   RAM     2114       ICs 51&52   X

Any memory access to an address indicated by an x will cause IC5 to generate an 'on card' signal, and disable the off card address and data bus buffers.