
ARNOS INSTRUMENTS & COMPUTER SYSTEMS, INC.

A486-25/33/50C

Processor           80486SX/80487SX/80486DX/80486DX2
Processor Speed     25/33/50(internal)/50/66(internal)MHz
Chip Set            AIC
Max. Onboard DRAM   64MB
Cache               64/128/256/512/1024KB
BIOS                AMI/Phoenix
Dimensions          264mm x 219mm
I/O Options         None
NPU Options         4167

[Image]

                                CONNECTIONS

  Purpose                   Location   Purpose                   Location

  External battery            X8       Turbo switch                X15

  Reset switch                X13      Speaker                     X16

  Turbo LED                   X14      Power LED & keylock         X17

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Battery select internal                  S3            pins 1 & 2
                                                              closed

      Battery select external                  S3            pins 2 & 3
                                                              closed

     Battery type select 5VDC or less         S4            pins 1 & 2
                                                              closed

      Battery type select greater than         S4            pins 2 & 3
      5VDC                                                    closed

     External cache enabled                   S5              open

      External cache disabled                  S5             closed

     CPU speed select iOSC/2                  S7            pins 1 & 2
                                                              closed

      CPU speed select iOSC/1                  S7            pins 2 & 3
                                                              closed

     Monitor type select color                S8             closed

      Monitor type select monochrome           S8              open

                          CPU TYPE CONFIGURATION

        CPU Type                    S6                       S9

        80486DX2            pins 1 & 2 closed       pins 1 & 2 and 3 & 4
                                                           closed

         80486DX            pins 1 & 2 closed       pins 1 & 2 and 3 & 4
                                                           closed

         80487SX            pins 2 & 3 closed       pins 1 & 2 and 3 & 4
                                                           closed

         80486SX                   open              pins 2 & 3 closed

              DRAM CONFIGURATION

      Size          Bank 0          Bank 1

      1MB         (4) 256K x 9       NONE

      2MB         (4) 256K x 9   (4) 256K x 9

      4MB         (4) 1M x 9         NONE

      8MB         (4) 1M x 9      (4) 1M x 9

      16MB        (4) 4M x 9         NONE

      32MB        (4) 4M x 9      (4) 4M x 9

      64MB        (4) 16M x 9        NONE

                        CACHE JUMPER CONFIGURATION

     Size          S1          S2         S10         S12          S13

     64KB       pins 1 &    pins 1 &    pins 1 &    pins 1 &     pins 1 &
                   2           2           2           2            2

    128KB       pins 2 &    pins 1 &    pins 2 &    pins 1 &     pins 2 &
                   3           2           3           2            3

    256KB       pins 2 &    pins 1 &    pins 2 &    pins 2 &     pins 1 &
                   3           2           3           3            2

    512KB       pins 2 &    pins 2 &    pins 2 &    pins 2 &     pins 1 &
                   3           3           3           3            2

    1024KB      pins 2 &    pins 2 &    pins 2 &    pins 2 &     pins 2 &
                   3           3           3           3            3

  Note:Pins designated should be in the closed position.

                      CACHE CONFIGURATION

      Size           Cache         Location          TAG

      64KB        (8) 8K x 8      Banks 0 & 1     (2) 8K x 8

     128KB        (4) 32K x 8       Bank 0        (2) 8K x 8

     256KB        (8) 32K x 8     Banks 0 & 1    (2) 32K x 8

     512KB       (4) 128K x 8       Bank 0       (2) 32K x 8

     1024KB      (8) 128K x 8     Banks 0 & 1    (2) 128K x 8

