
TANDY/RADIO SHACK

3100, MMPC MODEL 10/20

SENSATION! (250-1651)

Processor           80486SX/80487SX/ODP486/80486DX2
Processor Speed     25/33/50(internal)/66(internal)MHz
Chip Set            Unidentified
Video Chip Set      Unidentified
Maximum Onboard     64MB
Memory
Maximum Video       1MB
Memory
Cache               None
BIOS                Unidentified
Dimensions          254mm x 218mm
I/O Options         Floppy drive interface, IDE interface, parallel port,
                    PS/2 mouse port, serial ports (2), VGA feature
                    connector, VGA port, riser slot
NPU Options         None

[Image]

                                CONNECTIONS

  Purpose                  Location   Purpose                    Location

  VGA port                   CN1      IDE interface                CN6

  Parallel port              CN2      Floppy drive interface       CN7

  Serial port 2              CN3      VGA feature connector        CN8

  Serial port 1              CN4      Riser slot                   SL1

  PS/2 mouse port            CN5      IDE interface LED            W2

                        USER CONFIGURABLE SETTINGS

                Function                     Label           Position

      Parallel port IRQ select IRQ7           W5            Pins 1 & 2
                                                              closed

      Parallel port IRQ select IRQ5           W5            Pins 2 & 3
                                                              closed

      Parallel port IRQ disabled              W5               Open

     On board video enabled                  W8            Pins 2 & 3
                                                              closed

      On board video disabled                 W8            Pins 1 & 2
                                                              closed

     VGA IRQ disabled                        W9               Open

      VGA IRQ enabled                         W9              Closed

                            DRAM CONFIGURATION

     Size         Bank 0        Bank 1         Bank 2          Bank 3

     4MB        (1) 1M x 32      None           None            None

     5MB        (1) 1M x 32    (1) 256K x       None            None
                                  32

     6MB        (1) 1M x 32    (1) 256K x     (1) 256K x        None
                                  32             32

     6MB        (1) 1M x 32    (1) 512K x       None            None
                                  32

     7MB        (1) 1M x 32    (1) 256K x     (1) 256K x    (1) 256K x 32
                                  32             32

     7MB        (1) 1M x 32    (1) 512K x     (1) 256K x        None
                                  32             32

     8MB        (1) 1M x 32    (1) 512K x     (1) 256K x    (1) 256K x 32
                                  32             32

     8MB        (1) 1M x 32      None         (1) 512K x    (1) 512K x 32
                                                 32

     8MB        (1) 1M x 32   (1) 1M x 32       None            None

     8MB        (1) 2M x 32      None           None            None

     9MB        (1) 1M x 32    (1) 256K x     (1) 512K x    (1) 512K x 32
                                  32             32

     9MB        (1) 1M x 32   (1) 1M x 32     (1) 256K x        None
                                                 32

     9MB        (1) 2M x 32    (1) 256K x       None            None
                                  32

     10MB       (1) 1M x 32    (1) 512K x     (1) 512K x    (1) 512K x 32
                                  32             32

     10MB       (1) 1M x 32   (1) 1M x 32     (1) 256K x    (1) 256K x 32
                                                 32

     10MB       (1) 1M x 32   (1) 1M x 32     (1) 512K x        None
                                                 32

     10MB       (1) 2M x 32      None         (1) 256K x    (1) 256K x 32
                                                 32

     10MB       (1) 2M x 32    (1) 512K x       None            None
                                  32

     11MB       (1) 1M x 32   (1) 1M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     11MB       (1) 2M x 32    (1) 256K x     (1) 256K x    (1) 256K x 32
                                  32             32

     11MB       (1) 2M x 32    (1) 512K x     (1) 256K x        None
                                  32             32

     12MB       (1) 1M x 32   (1) 1M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     12MB       (1) 1M x 32   (1) 1M x 32    (1) 1M x 32        None

     12MB       (1) 2M x 32    (1) 512K x     (1) 256K x    (1) 256K x 32
                                  32             32

     12MB       (1) 2M x 32      None         (1) 512K x    (1) 512K x 32
                                                 32

     12MB       (1) 2M x 32   (1) 1M x 32       None            None

     13MB       (1) 1M x 32   (1) 1M x 32    (1) 1M x 32    (1) 256K x 32

     13MB       (1) 2M x 32    (1) 256K x     (1) 512K x    (1) 512K x 32
                                  32             32

     13MB       (1) 2M x 32   (1) 1M x 32     (1) 256K x        None
                                                 32

     14MB       (1) 1M x 32   (1) 1M x 32    (1) 1M x 32    (1) 512K x 32

     14MB       (1) 2M x 32    (1) 512K x     (1) 512K x    (1) 512K x 32
                                  32             32

     14MB       (1) 2M x 32   (1) 1M x 32     (1) 256K x    (1) 256K x 32
                                                 32

                        DRAM CONFIGURATION (CONT)

     Size         Bank 0        Bank 1         Bank 2          Bank 3

     14MB       (1) 2M x 32   (1) 1M x 32     (1) 512K x        None
                                                 32

     15MB       (1) 2M x 32   (1) 1M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     16MB       (1) 1M x 32   (1) 1M x 32    (1) 1M x 32     (1) 1M x 32

     16MB       (1) 2M x 32   (1) 1M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     16MB       (1) 2M x 32      None        (1) 1M x 32     (1) 1M x 32

     16MB       (1) 2M x 32   (1) 2M x 32       None            None

     16MB       (1) 4M x 32      None           None            None

     17MB       (1) 2M x 32    (1) 256K x    (1) 1M x 32     (1) 1M x 32
                                  32

     17MB       (1) 2M x 32   (1) 2M x 32     (1) 256K x        None
                                                 32

     17MB       (1) 4M x 32    (1) 256K x       None            None
                                  32

     18MB       (1) 2M x 32    (1) 512K x    (1) 1M x 32     (1) 1M x 32
                                  32

     18MB       (1) 2M x 32   (1) 2M x 32     (1) 256K x    (1) 256K x 32
                                                 32

     18MB       (1) 2M x 32   (1) 2M x 32     (1) 512K x        None
                                                 32

     18MB       (1) 4M x 32    (1) 256K x     (1) 256K x        None
                                  32             32

     18MB       (1) 4M x 32    (1) 512K x       None            None
                                  32

     19MB       (1) 2M x 32   (1) 2M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     19MB       (1) 4M x 32    (1) 256K x     (1) 256K x    (1) 256K x 32
                                  32             32

     19MB       (1) 4M x 32    (1) 512K x     (1) 256K x        None
                                  32             32

     20MB       (1) 2M x 32   (1) 1M x 32    (1) 1M x 32     (1) 1M x 32

     20MB       (1) 2M x 32   (1) 2M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     20MB       (1) 2M x 32   (1) 2M x 32    (1) 1M x 32        None

     20MB       (1) 4M x 32    (1) 512K x     (1) 256K x    (1) 256K x 32
                                  32             32

     20MB       (1) 4M x 32      None         (1) 512K x    (1) 512K x 32
                                                 32

     20MB       (1) 4M x 32   (1) 1M x 32       None            None

     21MB       (1) 2M x 32   (1) 2M x 32    (1) 1M x 32    (1) 256K x 32

     21MB       (1) 4M x 32    (1) 256K x     (1) 512K x    (1) 512K x 32
                                  32             32

     21MB       (1) 4M x 32   (1) 1M x 32     (1) 256K x        None
                                                 32

     22MB       (1) 2M x 32   (1) 2M x 32    (1) 1M x 32    (1) 512K x 32

     22MB       (1) 4M x 32    (1) 512K x     (1) 512K x    (1) 512K x 32
                                  32             32

     22MB       (1) 4M x 32   (1) 1M x 32     (1) 256K x    (1) 256K x 32
                                                 32

     22MB       (1) 4M x 32   (1) 1M x 32     (1) 512K x        None
                                                 32

     23MB       (1) 4M x 32   (1) 1M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     24MB       (1) 2M x 32   (1) 2M x 32    (1) 1M x 32     (1) 1M x 32

     24MB       (1) 2M x 32   (1) 2M x 32    (1) 2M x 32        None

     24MB       (1) 4M x 32   (1) 1M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     24MB       (1) 4M x 32   (1) 1M x 32    (1) 1M x 32        None

     24MB       (1) 4M x 32   (1) 2M x 32       None            None

     25MB       (1) 2M x 32   (1) 2M x 32    (1) 2M x 32    (1) 256K x 32

     25MB       (1) 4M x 32   (1) 1M x 32    (1) 1M x 32    (1) 256K x 32

     25MB       (1) 4M x 32   (1) 2M x 32     (1) 256K x        None
                                                 32

     26MB       (1) 2M x 32   (1) 2M x 32    (1) 2M x 32    (1) 512K x 32

     26MB       (1) 4M x 32   (1) 1M x 32    (1) 1M x 32    (1) 512K x 32

                        DRAM CONFIGURATION (CONT)

     Size         Bank 0        Bank 1         Bank 2          Bank 3

     26MB       (1) 4M x 32   (1) 2M x 32     (1) 256K x    (1) 256K x 32
                                                 32

     26MB       (1) 4M x 32   (1) 2M x 32     (1) 512K x        None
                                                 32

     27MB       (1) 4M x 32   (1) 2M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     28MB       (1) 2M x 32   (1) 2M x 32    (1) 2M x 32     (1) 1M x 32

     28MB       (1) 4M x 32   (1) 1M x 32    (1) 1M x 32     (1) 1M x 32

     28MB       (1) 4M x 32   (1) 2M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     28MB       (1) 4M x 32   (1) 2M x 32    (1) 1M x 32        None

     29MB       (1) 4M x 32   (1) 2M x 32    (1) 1M x 32    (1) 256K x 32

     30MB       (1) 4M x 32   (1) 2M x 32    (1) 1M x 32    (1) 512K x 32

     32MB       (1) 2M x 32   (1) 2M x 32    (1) 2M x 32     (1) 2M x 32

     32MB       (1) 4M x 32   (1) 2M x 32    (1) 1M x 32     (1) 1M x 32

     32MB       (1) 4M x 32      None        (1) 2M x 32     (1) 2M x 32

     32MB       (1) 4M x 32   (1) 4M x 32       None            None

     33MB       (1) 4M x 32    (1) 256K x    (1) 2M x 32     (1) 2M x 32
                                  32

     33MB       (1) 4M x 32   (1) 4M x 32     (1) 256K x        None
                                                 32

     34MB       (1) 4M x 32    (1) 512K x    (1) 2M x 32     (1) 2M x 32
                                  32

     34MB       (1) 4M x 32   (1) 4M x 32     (1) 256K x    (1) 256K x 32
                                                 32

     34MB       (1) 4M x 32   (1) 4M x 32     (1) 512K x        None
                                                 32

     35MB       (1) 4M x 32   (1) 4M x 32     (1) 512K x    (1) 256K x 32
                                                 32

     36MB       (1) 4M x 32   (1) 1M x 32    (1) 2M x 32     (1) 2M x 32

     36MB       (1) 4M x 32   (1) 4M x 32     (1) 512K x    (1) 512K x 32
                                                 32

     36MB       (1) 4M x 32   (1) 4M x 32    (1) 1M x 32        None

     37MB       (1) 4M x 32   (1) 4M x 32    (1) 1M x 32    (1) 256K x 32

     38MB       (1) 4M x 32   (1) 4M x 32    (1) 1M x 32    (1) 512K x 32

     40MB       (1) 4M x 32   (1) 2M x 32    (1) 2M x 32     (1) 2M x 32

     40MB       (1) 4M x 32   (1) 4M x 32    (1) 1M x 32     (1) 1M x 32

     40MB       (1) 4M x 32   (1) 4M x 32    (1) 2M x 32        None

     41MB       (1) 4M x 32   (1) 4M x 32    (1) 2M x 32    (1) 256K x 32

     42MB       (1) 4M x 32   (1) 4M x 32    (1) 2M x 32    (1) 512K x 32

     44MB       (1) 4M x 32   (1) 4M x 32    (1) 2M x 32     (1) 1M x 32

     48MB       (1) 4M x 32   (1) 4M x 32    (1) 2M x 32     (1) 2M x 32

     48MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32        None

     49MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32    (1) 256K x 32

     50MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32    (1) 512K x 32

     52MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32     (1) 1M x 32

     56MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32     (1) 2M x 32

     64MB       (1) 4M x 32   (1) 4M x 32    (1) 4M x 32     (1) 4M x 32

                  VIDEO MEMORY CONFIGURATION

        Size                Bank 0               Bank 1

        512KB               512KB                 None

         1MB                512KB                512KB

  Note: The size of the video memory chips are unidentified.

  CPU SPEED SELECTION

   Speed         W1

   25MHz       Closed

   33MHz        Open

   50iMHz      Closed

   66iMHz       Open

                      CPU TYPE SELECTION

        Type                  W6                   W7

       80486SX         Pins 2 & 3 closed   Pins 1 & 2 closed

       80487SX         Pins 1 & 2 closed   Pins 2 & 3 closed

       ODP486          Pins 1 & 2 closed   Pins 1 & 2 closed

       80486DX         Pins 1 & 2 closed   Pins 1 & 2 closed

      80486DX2         Pins 1 & 2 closed   Pins 1 & 2 closed

  Note: W7 may not be present on all boards.

                      SERIAL PORT 1 ADDRESS SELECTION

           Setting                     IRQ                    W3

            COM1/COM3                IRQ4            Pins 1 & 2 closed

               COM3                   IRQ11           Pins 2 & 3 closed

                      SERIAL PORT 2 ADDRESS SELECTION

           Setting                     IRQ                    W4

        COM2/COM4 (2F8h)             IRQ3            Pins 1 & 2 closed

               COM4                   IRQ10           Pins 2 & 3 closed

