
UNIDENTIFIED

TURBO MAINBOARD (4.77/10MHZ)

Processor              8088
Processor Speed        4.77/10MHz
Chip Set               Unidentified
Video Chip Set         None
Maximum Onboard Memory 640KB
Maximum Video Memory   None
Cache                  None
BIOS                   Unidentified
Dimensions             276mm x 196mm
I/O Options            None
NPU Options            8087

[Image]

                                CONNECTIONS

  Purpose                Location      Purpose                Location

  Speaker                  JP1         Turbo LED            JP5 pins 1 &
                                                                 2

  Keylock                  JP3         Power LED            JP5 pins 3 &
                                                                 4

  Reset switch             JP4         Turbo switch             JP6

                        USER CONFIGURABLE SETTINGS

                Function                     Label           Position

     Factory configured - do not alter      SW1/1             Off

     NPU not installed                      SW1/2              On

      NPU installed                          SW1/2             Off

     Factory configured - do not alter      SW1/3             Off

     Factory configured - do not alter      SW1/4             Off

                            DRAM CONFIGURATION

   Size      Bank 0     Bank 1     Bank 2    Bank 2A   Bank 3    Bank 3A

  256KB        (9)       None       None      None      None       None
             41256

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

  576KB        (9)        (9)        (2)       (1)      None       None
             41256      41256       4464      4164

  640KB        (9)        (9)        (2)       (1)       (2)     (1) 4164
             41256      41256       4464      4164      4464

                  FLOPPY DRIVE SELECTION

  Drives installed         SW1/7               SW1/8

         1                  On                  On

         2                  Off                 On

         3                  On                  Off

         4                  Off                 Off

                   MONITOR SELECTION

       Type              SW1/5              SW1/6

       None                On                 On

  Color (40 x 20)         Off                 On

  Color (80 x 25)          On                Off

    Monochrome            Off                Off

                              TURBO SELECTION

             Type                      JP7                   JP8

     Always in turbo mode       Pins 1 & 2 closed     Pins 2 & 3 closed

     Turbo select through       Pins 2 & 3 closed     Pins 1 & 2 closed
           software

     Turbo select through       Pins 1 & 2 closed     Pins 1 & 2 closed
     software & keyboard

            Note: To toggle between normal and turbo modes, press CTRL,
            ALT, + to enable turbo and CTRL, ALT, - to disable turbo.

