
JETPRO INFOTECH COMPANY, LTD.

MB-4F

Processor             80386DX/CX486DLC/80486SX/80487SX/80486DX/80486DX2
Processor Speed       20/25/33/40/50(internal)/66(internal)
Chip Set              FOREX
Max. Onboard DRAM     32MB
SRAM Cache            64/128/256KB
BIOS                  AMI/AWARD
Dimensions            220mm x 340mm
I/O Options           None
NPU Options           80387

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                  Location

  External battery            JP2       Turbo switch              JP15

  Reset switch                JP8       Turbo LED                 JP16

  Power LED & keylock         JP14      Speaker                   JP17

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Parity check enabled                     JP5            closed

      Parity check disabled                    JP5             open

     Monitor type select color                JP6            closed

      Monitor type select monochrome           JP6             open

     Factory configured - do not alter       JP19             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

                          CPU TYPE CONFIGURATION

      CPU         JP12       JP13       JP30      W1A-W1G       W2A-W2H

   80486DX2       pins 1    pins 1     pins 1    pins 1 & 2   pins 1 & 2
                   & 2       & 2        & 2

    80486DX       pins 1    pins 1     pins 1    pins 1 & 2   pins 1 & 2
                   & 2       & 2        & 2

    80487SX       pins 1    pins 1     pins 2    pins 1 & 2   pins 1 & 2
                   & 2       & 2        & 3

    80486SX       pins 2    pins 2     pins 2    pins 1 & 2   pins 1 & 2
                   & 3       & 3        & 3

    80386DX        N/A       N/A        N/A      pins 2 & 3   pins 2 & 3

  Note:Pins designated should be in the closed position.

                            SRAM CONFIGURATION

     Size        Cache SRAM      Location      TAG(U26)       TAG(U42)

     64KB        (8) 8K x 8    Banks 0 & 1    (1) 8K x 8        NONE

     128KB      (4) 32K x 8       Bank 0      (1) 8K x 8        NONE

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

  Note:The exact locations of U26 and U42 are unknown.

                         SRAM JUMPER CONFIGURATION

   Size       JP8A       JP8B      JP8C      JP8D       JP8E       JP8F

   64KB       pins 2    pins 2     pins 1    pins 2    pins 2    pins 1 &
               & 3       & 3        & 2       & 3       & 3         2

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

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

  Note:Pins designated should be in the closed position.

