QUATECH, INC.

PXB-721

Card Type          I/O controller
Chipset/Controller Intel
I/O Options        8255 I/O ports (3)
Maximum DRAM       N/A

[Image]

                                CONNECTIONS

         Purpose           Location          Purpose            Location

  34-pin 8255 interface      H1       34-pin 8255 interface 3      H3
  1

  34-pin 8255 interface      H2
  2

                      BASE MEMORY ADDRESS SELECT

  Address    SW1/1     SW1/2     SW1/3     SW1/4     SW1/5     SW1/6

   230h       Off        On        On        On       Off       Off

   260h       Off        On        On       Off       Off        On

   2E0h       Off        On       Off       Off       Off        On

   300h       Off       Off        On        On        On        On

   350h       Off       Off        On       Off        On       Off

         EXTERNAL INTERRUPT EDGE

        Edge                  J1

       Rising         Pins 1 & 3 closed

       Falling        Pins 1 & 2 closed

                             INTERRUPT SELECT

    IRQ        J5/A      J5/B      J5/C       J5/D      J5/E       J5/F

  IR/FONT>     Open      Open      Open       Open      Open      Closed

    IRQ3       Open      Open      Open       Open     Closed      Open

    IRQ4       Open      Open      Open      Closed     Open       Open

    IRQ5       Open      Open     Closed      Open      Open       Open

    IRQ6       Open     Closed     Open       Open      Open       Open

    IRQ7      Closed     Open      Open       Open      Open       Open

                PORT 1 INTERRUPT SELECT

            IRQ                         J2

             A               Pins 2 & 3, 4 & 5 closed

             B               Pins 1 & 2, 5 & 6 closed

                PORT 2 INTERRUPT SELECT

            IRQ                         J3

             A               Pins 2 & 3, 4 & 5 closed

             B               Pins 1 & 2, 5 & 6 closed

                PORT 3 INTERRUPT SELECT

            IRQ                         J4

             A               Pins 2 & 3, 4 & 5 closed

             B               Pins 1 & 2, 5 & 6 closed