STANDARD MICROSYSTEMS CORPORATION

ARCNET PC250

NIC Type              Arcnet
Chipset               SMC 9026, 9032
Network Transfer Rate 2.5Mbps
Data Bus              8-bit ISA
Topology              Linear Bus/Star
Wire Type             Unshielded twisted pair
Boot ROM              Available

[Image]

                                CONNECTIONS

         Function            Label            Function             Label

  Unshielded twisted pair      J1      Unshielded twisted pair      J2
  connector                            connector

                            INTERRUPT

  Setting      JP3        JP4        JP5        JP6       JP7

   IRQ2      Closed      Open       Open       Open       Open

   IRQ3       Open      Closed      Open       Open       Open

   IRQ4       Open       Open      Closed      Open       Open

   IRQ5       Open       Open       Open      Closed      Open

   IRQ7       Open       Open       Open       Open      Closed

                       EXTENDED RANGE CONFIGURATION

    Response Time        Recon Time           JP1               JP2

  »       75.7 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

   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

   254       On     Off     Off     Off     Off     Off     Off      Off

            Note: A total of 254 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 ID. (Off=1, On=0)

            Node addresses 0 and 255 are reserved and should not be used.

                             BASE I/O ADDRESS

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

       000h      On        On        On         On        On        On

       010h      On        On        On         On        On        Off

       020h      On        On        On         On       Off        On

       030h      On        On        On         On       Off        Off

       040h      On        On        On        Off        On        On

  »    2E0h      Off       On        Off       Off       Off        On

       3B0h      Off       Off       Off        On       Off        Off

       3C0h      Off       Off       Off       Off        On        On

       3D0h      Off       Off       Off       Off        On        Off

       3E0h      Off       Off       Off       Off       Off        On

       3F0h      Off       Off       Off       Off       Off        Off

            Note: A total of 64 base address settings are available. The
            switches are a binary representation of the decimal memory
            addresses. SW1/1 is the Most Significant Bit and switch SW1/6
            is the Least Significant Bit. The switches have the following
            decimal values: SW1/1=512, SW1/2=256, SW1/3=128, SW1/4=64,
            SW1/5=32, SW1/6=16. Turn off the switches and add the values
            of the switches that are off to obtain the correct memory
            address. (Off=1, On=0)

                  SHARED RAM ADDRESS

  Setting    SW2/7      SW2/8      SW2/9     SW2/10

  00000h      Off        Off        Off        Off

  10000h      Off        Off        Off        On

  20000h      Off        Off        On         Off

  30000h      Off        Off        On         On

  40000h      Off         On        Off        Off

  50000h      Off         On        Off        On

  60000h      Off         On        On         Off

  70000h      Off         On        On         On

  80000h       On        Off        Off        Off

  90000h       On        Off        Off        On

  A0000h       On        Off        On         Off

  B0000h       On        Off        On         On

  C0000h       On         On        Off        Off

  D0000h       On         On        Off        On

  E0000h       On         On        On         Off

  F0000h       On         On        On         On