MODULAR CIRCUIT TECHNOLOGY

JDR C486-33/50/66

Processor         80486SX/80486DX/80486DX2
Processor Speed   33/66(internal)MHz
Chip Set          UMC
Max. Onboard DRAM 32MB
Cache             64/128/256KB
BIOS              AMI
Dimensions        254mm x 218mm
I/O Options       None
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                    Location   Purpose                  Location

  Speaker                      J1       Turbo LED                  J4

  Reset connector              J2       External battery           J8

  Power LED & keylock          J3

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

  »   CMOS memory normal operation             J7              Open

      CMOS memory clear                        J7           pins 2 & 3
                                                              closed

  »   Factory configured - do not             JP4              Open
      alter

  »   Factory configured - do not             JP5              Open
      alter

  »   Factory configured - do not             JP6             Closed
      alter

  »   Factory configured - do not             JP7              Open
      alter

  »   Monitor type select color               JP9             Closed

      Monitor type select monochrome          JP9              Open

              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

      5MB         (4) 256K x 9    (4) 1M x 9

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

      16MB        (4) 4M x 9         NONE

      20MB        (4) 1M x 9      (4) 4M x 9

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

                    CACHE CONFIGURATION

     Size          Bank 0         Bank 1          TAG

     64KB        (4) 8K x 8     (4) 8K x 8    (1) 8K x 8

     128KB      (4) 32K x 8        NONE       (1) 8K x 8

     256KB      (4) 32K x 8    (4) 32K x 8    (1) 32K x 8

                        CACHE JUMPER CONFIGURATION

     Size           W1             W2             W3             W4

     64KB        pins 2 & 3       Open           Open         pins 1 & 2
                  closed                                       closed

    128KB        pins 1 & 2       Open          Closed        pins 2 & 3
                  closed                                       closed

    256KB        pins 2 & 3      Closed         Closed        pins 2 & 3
                  closed                                       closed

                          CPU TYPE CONFIGURATION

        Type                JP1               JP2               JP3

     80486SX-33             Open           pins 2 & 3           Open
                                             closed

     80486DX-33          pins 1 & 2        pins 1 & 2          Closed
                           closed            closed

     80486DX2-66         pins 1 & 2        pins 1 & 2          Closed
                           closed            closed

      CPU TYPE CONFIGURATION

    Type       JP10        JP11

  80486DX     Closed       Open

  80486DX2    Closed      Closed