THOMAS-CONRAD CORPORATION

TC6844 ARC CARD/SE30

NIC Type              ArcNet
Chip Set              NCR 90C26
Data Bus              Mac SE/30
Network Transfer Rate 2.5Mbps
Topology              Linear Bus
Wiring Type           RG-62A/U 93ohm coaxial
Boot ROM              Not available

[Image]

                                CONNECTIONS

         Function             Label            Function            Label

  Header to connector card     J1A     RG-62A/U 93ohm coaxial       J2
                                       connector

  Header to main board         J1B

                       EXTENDED RANGE CONFIGURATION

   Response Time        Recon Time           JP1               JP2

      74.7 uS             840 mS            Open               Open

      283.4 uS            1.68 S           Closed              Open

      561.8 uS            1.68 S            Open              Closed

     1.1186 mS            1.68 S           Closed             Closed

            Note:This setting should only be changed when the length of
            the ArcNet segments exceed 6000 meters.

                               NODE ADDRESS

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

    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

    5       Off      On     Off      On      On      On      On      On

   249      Off      On      On     Off     Off     Off     Off      Off

   250       On     Off      On     Off     Off     Off     Off      Off

   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

            Note: A total of 253 node address settings are available. The
            switches are a binary representation of the decimal node
            addresses. SW1/8 is the Most Significant Bit and switch SW1/1
            is the Least Significant Bit. The switches have the following
            decimal values: SW1/8=128, SW1/7=64, SW1/6=32, SW1/5=16,
            SW1/4=8, SW1/3=4, SW1/2=2, SW1/1=1. Turn off the switches and
            add the values of the switches that are off to obtain the
            correct node address. (Off=1, On=0)

            Addresses 0, 254, and 255 are reserved and should not be
            used.