UNIDENTIFIED

TURBO MAINBOARD

Processor              8088
Processor Speed        4.77/8MHz
Chip Set               Unidentified
Video Chip Set         None
Maximum Onboard Memory 640KB
Maximum Video Memory   None
Cache                  None
BIOS                   Unidentified
Dimensions             330mm x 218mm
I/O Options            None
NPU Options            8087

[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Operating mode              P3       Keyboard connector          P5
  interface

  Speaker                     P4       Reset switch                SW2

                        USER CONFIGURABLE SETTINGS

                 Function                     Label          Position

      I/O address is C0H (bit 0 low =           E1           Pins 1 & 2
      turbo mode; high = normal mode)                         closed

      I/O address is 061H (bit 2 low =          E1           Pins 2 & 3
      turbo mode; high = normal mode)                         closed

      CPU changes speed during disk             E6            Closed
      drive access

      CPU does not change speed during          E6             Open
      disk drive access

      Boot memory test enabled                SW1/1             On

      Boot memory test disabled               SW1/1             Off

      NPU not installed                       SW1/2             On

      NPU installed                           SW1/2             Off

                       DRAM CONFIGURATION

    Size        Bank 0       Bank 1      Bank 2       Bank 3

    64KB       (9) 4164       None        None         None

    128KB      (9) 4164     (9) 4164      None         None

    192KB      (9) 4164     (9) 4164    (9) 4164       None

    256KB      (9) 4164     (9) 4164    (9) 4164     (9) 4164

    256KB     (9) 41256       None        None         None

    512KB     (9) 41256    (9) 41256      None         None

    576KB     (9) 41256    (9) 41256    (9) 4164       None

    640KB     (9) 41256    (9) 41256    (9) 4164     (9) 4164

   DRAM JUMPER/SWITCH CONFIGURATION

   Size      E4       SW1/3    SW1/4

   64KB     Open       On        On

  128KB     Open       Off       On

  192KB     Open       On       Off

  256KB     Open       Off      Off

  256KB    Closed      On        On

  512KB    Closed      Off       On

  576KB    Closed      On       Off

  640KB    Closed      Off      Off

                  FLOPPY DRIVE SELECTION

  Drives installed         SW1/7               SW1/8

         1                  On                  On

         2                  On                  Off

         3                  Off                 On

         4                  Off                 Off

                   MONITOR SELECTION

       Type              SW1/5              SW1/6

       None                On                 On

  Color (80 x 25)          On                Off

  Color (40 x 25)         Off                 On

    Monochrome            Off                Off

                               ROM SELECTION

    U25 address        U26 address            E2                E3

  F6000H - FDFFFH    FE000H - FFFFFH        Closed            Closed

  F4000H - FBFFFH    FC0000H - FFFFFH       Closed             Open

  F0000H - F7FFFH    F8000H - FFFFFH         Open              Open