
STANDARD MICROSYSTEMS CORPORATION

ARCNET PC220

NIC Type              ARCnet
Network Transfer Rate 2.5Mbps
Data Bus              16-bit ISA
Topology              Linear Bus
Wiring Type           RG-62A/U 93ohm coaxial
Boot ROM              Available

[Image]

                         CONNECTIONS

           Function                        Label

  RG-62A/U 93ohm coaxial port                J1

                        USER CONFIGURABLE SETTINGS

                  Function                      Label        Position

      Factory configured - do not alter         EXT           Open

      Boot ROM enabled                          ROM          Closed

       Boot ROM disabled                         ROM           Open

  Note: Jumper EXT is used to configure the network time-out settings,
  these two jumpers are normally left open, however for additional
  settings refer to the COM 9026 Data Sheet.

                          NODE ADDRESS SELECTION

  Setting    S1/1   S1/2    S1/3    S1/4    S1/5    S1/6    S1/7    S1/8

     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

    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

            Note: A total of 255 node address settings are available. The
            switches are a binary representation of the decimal memory
            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 to obtain the correct node
            address.

                        BASE I/O ADDRESS SELECTION

   Address      S2/6      S2/5      S2/4      S2/3      S2/2       S2/1

     0h          On        On        On        On        On         On

     10h         On        On        On        On        On        Off

     20h         On        On        On        On        Off        On

     30h         On        On        On        On        Off       Off

     40h         On        On        On        Off       On         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 I/O address settings are available.
            The switches are a binary representation of the decimal
            memory addresses. SW2/1 is the Most Significant Bit and
            switch SW2/6 is the Least Significant Bit. The switches have
            the following decimal values: SW2/1=512, SW2/2=256,
            SW2/3=128, SW2/4=64, SW2/5=32, SW2/6=16. Turn off the
            switches and add the values of the switches to obtain the
            correct node address.

                       INTERRUPT SELECTION

    IRQ       IRQ/A      IRQ/B      IRQ/C      IRQ/D     IRQ/E

    2/9      Closed      Open       Open       Open       Open

     3        Open      Closed      Open       Open       Open

     4        Open       Open      Closed      Open       Open

     5        Open       Open       Open      Closed      Open

     7        Open       Open       Open       Open      Closed

                       BASE MEMORY ADDRESS SELECTION

  Address   SW3/1   SW3/2   SW3/3   SW3/4   SW3/5   SW3/6   SW3/7   SW3/8

   000h      On      On      On      On      On      On      On      On

   800h      On      On      On      On      On      On      On      Off

  1000h      On      On      On      On      On      On     Off      On

  1800h      On      On      On      On      On      On     Off      Off

  4000h      On      On      On      On      On     Off      On      On

  4800h      On      On      On      On      On     Off      On      Off

  5000h      On      On      On      On      On     Off     Off      On

  5800h      On      On      On      On      On     Off     Off      Off

  8000h      On      On      On      On     Off      On      On      On

  8800h      On      On      On      On     Off      On      On      Off

  9000h      On      On      On      On     Off      On     Off      On

  9800h      On      On      On      On     Off      On     Off      Off

  C000h      On      On      On      On     Off     Off      On      On

  C800h      On      On      On      On     Off     Off      On      Off

  D000h      On      On      On      On     Off     Off     Off      On

  D800h      On      On      On      On     Off     Off     Off      Off

  F0000h    Off     Off     Off     Off      On      On      On      On

  F0800h    Off     Off     Off     Off      On      On      On      Off

  F1000h    Off     Off     Off     Off      On      On     Off      On

  F1800h    Off     Off     Off     Off      On      On     Off      Off

  F4000h    Off     Off     Off     Off      On     Off      On      On

  F4800h    Off     Off     Off     Off      On     Off      On      Off

  F5000h    Off     Off     Off     Off      On     Off     Off      On

  F5800h    Off     Off     Off     Off      On     Off     Off      Off

  F8000h    Off     Off     Off     Off     Off      On      On      On

  F8800h    Off     Off     Off     Off     Off      On      On      Off

  F9000h    Off     Off     Off     Off     Off      On     Off      On

  F9800h    Off     Off     Off     Off     Off      On     Off      Off

  FC000h    Off     Off     Off     Off     Off     Off      On      On

  FC800h    Off     Off     Off     Off     Off     Off      On      Off

  FD000h    Off     Off     Off     Off     Off     Off     Off      On

  FD800h    Off     Off     Off     Off     Off     Off     Off      Off

            Note: The above table includes only a few of the many memory
            address settings available. The switches are a binary
            representation of the decimal memory addresses. SW3/1 is the
            Most Significant Bit and switch SW3/8 is the Least
            Significant Bit. The switches have the following decimal
            values: SW3/8=2048, SW3/7=4096, SW3/6=16384, SW3/5=32768,
            SW3/4=65536, SW3/3=131072, SW3/2=262144, SW3/1=524288. Turn
            off the switches and add the values of the switches to obtain
            the correct address.

            Notice that there is no switch representation for 8192
            decimal. This means that 02000h, 03000h, 06000h, 07000h,
            0A000h, 0B000h and 0E000h cannot be represented. Omissions in
            the above table reflect this.

