
GATEWAY COMMUNICATIONS, INC.

G/NET (REV.02 AND BELOW)

NIC Type      G-Net
Transfer Rate 2.5Mbps
Data Bus      8-bit ISA
Topology      Linear Bus
Wiring Type   RG--11/U 75ohm coaxial

              RG-59/U 75ohm coaxial

              RG-62A/U 93ohm coaxial
Boot ROM      Not available (optional card required)

[Image]

                               NODE ADDRESS

  Node   SW1/1    SW1/2   SW1/3   SW1/4    SW1/5   SW1/6    SW1/7   SW1/8

   0       -       -        -       -       -        -       -        -

   1      Off      On      On      On       On      On       On      On

   2      On      Off      On      On       On      On       On      On

   3      Off     Off      On      On       On      On       On      On

   4      On       On      Off     On       On      On       On      On

  251     Off     Off      On      Off     Off      Off     Off      Off

  252     On       On      Off     Off     Off      Off     Off      Off

  253     Off      On      Off     Off     Off      Off     Off      Off

  254     On      Off      Off     Off     Off      Off     Off      Off

  255     Off     Off      Off     Off     Off      Off     Off      Off

  Notes: Node address 0 is used for messaging between nodes and must not
  be used.

  A total of 255 node address settings are available. The switches are a
  binary representation of the decimal node addresses. Switch 1 is the
  Least Significant Bit and switch 8 is the Most Significant Bit. The
  switches have the following decimal values: switch 1=1, 2=2, 3=4, 4=8,
  5=16, 6=32, 7=64, 8=128. Turn off the switches and add the values of
  the off switches to obtain the correct node address.

  (On=0, off=1)

                                CABLE TYPE

                  Type                                  JP1

       RG11/U 75ohm or RG-59/U 75ohm                 Closed

               RG-62A/U 93ohm                          Open

                             INTERRUPT REQUEST

          IRQ                      JP2                      JP3

             4             Pins 2 & 3 closed          All pins open

              2               All pins open          Pins 2 & 3 closed

              3             Pins 1 & 2 closed          All pins open

              5               All pins open          Pins 1 & 2 closed

                        BASE MEMORY BUFFER ADDRESS

      Address          SW2/1         SW2/2         SW2/3         SW2/4

        D0000h         Off           On            Off           Off

         50000h         Off           On            Off           On

         60000h          On           Off           Off           On

         70000h         Off           Off           Off           On

         80000h          On           On            On            Off

         90000h         Off           On            On            Off

         A0000h          On           Off           On            Off

         C0000h          On           On            Off           Off

         E0000h          On           Off           Off           Off

                             I/O BASE ADDRESS

       Address           SW2/5        SW2/6        SW2/7         SW2/8

       2E0h-2FFh         Off          Off          Off           On

        200h-21Fh          On           On           On           On

        220h-23Fh         Off           On           On           On

        240h-25Fh          On          Off           On           On

        260h-27Fh         Off          Off           On           On

        280h-29Fh          On           On          Off           On

        2A0h-2BFh         Off           On          Off           On

        2D0h-2DFh          On           On           On           On

        300h-31Fh          On           On           On           Off

        320h-33Fh         Off           On           On           Off

        340h-35Fh          On          Off           On           Off

        360h-37Fh         Off          Off           On           Off

        380h-39Fh          On           On          Off           Off

        3A0h-3BFh         Off           On          Off           Off

        3C0h-3DFh          On          Off          Off           Off

        3E0h-3FFh         Off          Off          Off           Off

                 CONNECTORS

       Purpose              Location

  Piggy-back Keycard           CN1

