
TANDY/RADIO SHACK

MEMORY EXPANSION BOARD (250-4030)

Card Type              Memory
Maximum Onboard Memory 2MB DRAM
Data Bus               16-bit ISA

[Image]

                        USER CONFIGURABLE SETTINGS

                   Setting                      Label        Position

     Factory configured - do not alter         S1/1            Off

     Factory configured - do not alter         S1/7            N/A

     Memory in Bank 1 enabled                  S1/8            Off

      Memory in Bank 1 disabled                 S1/8            On

            Note:Bank 1 should be disabled only if the board number is
            set to 1.

                            DRAM CONFIGURATION

     Size          Bank 0         Bank 1        Bank 2          Bank 3

     512KB       (18) 256K x       None          None            None
                     1

      1MB        (18) 256K x    (18) 256K x      None            None
                     1              1

     1.5MB       (18) 256K x    (18) 256K x   (18) 256K x        None
                     1              1              1

      2MB        (18) 256K x    (18) 256K x   (18) 256K x     (18) 256K x
                     1              1              1              1

            Note:The exact location of each bank is unidentified.

                           DRAM JUMPER SELECTION

            Size                      S1/5                   S1/6

              512KB                    On                     On

              1MB                    Off                     On

              1.5MB                    On                    Off

               2MB                    Off                    Off

                          BOARD NUMBER SELECTION

     Number          Address          S1/2         S1/3          S1/4

         1          100000h           On           On            On

          2          300000h          Off           On            On

          3          500000h           On           Off           On

          4          700000h          Off           Off           On

          5          900000h           On           On            Off

          6          B00000h          Off           On            Off

          7          D00000h           On           Off           Off

