CNET TECHNOLOGY, INC.
=====================

   CN120A, CN120AB, CN120AT, CN120SBT CN120ST, CN120TP

   NIC Type         ARCnet                                        
   Transfer Rate    2.5Mbps                                       
   Data Bus         8-bit ISA                                     
   Topology         Star                                          
                                                                  
                    Linear Bus                                    
   Wiring Type      RG-62A/U 93ohm coaxial                        
                                                                  
                    Unshielded twisted pair                       
   Boot ROM         Available                                     

<gopher://bitreich.org/I/th99/n/C-D/40002-1.png>
   

   +------------------------------------------------------------+
   |                        NODE ADDRESS                        |
   |------------------------------------------------------------|
   |Node |SW2/1 |SW2/2 |SW2/3 |SW2/4 |SW2/5 |SW2/6 |SW2/7 |SW2/8|
   |-----+------+------+------+------+------+------+------+-----|
   |  0  | N/A  | N/A  | N/A  | N/A  | N/A  | N/A  | N/A  | N/A |
   |-----+------+------+------+------+------+------+------+-----|
   |  1  |  On  | Off  | Off  | Off  | Off  | Off  | Off  | Off |
   |-----+------+------+------+------+------+------+------+-----|
   |  2  | Off  |  On  | Off  | Off  | Off  | Off  | Off  | Off |
   |-----+------+------+------+------+------+------+------+-----|
   |  3  |  On  |  On  | Off  | Off  | Off  | Off  | Off  | Off |
   |-----+------+------+------+------+------+------+------+-----|
   |  4  | Off  | Off  |  On  | Off  | Off  | Off  | Off  | Off |
   |-----+------+------+------+------+------+------+------+-----|
   | 251 |  On  |  On  | Off  |  On  |  On  |  On  |  On  | On  |
   |-----+------+------+------+------+------+------+------+-----|
   | 252 | Off  | Off  |  On  |  On  |  On  |  On  |  On  | On  |
   |-----+------+------+------+------+------+------+------+-----|
   | 253 |  On  | Off  |  On  |  On  |  On  |  On  |  On  | On  |
   |-----+------+------+------+------+------+------+------+-----|
   | 254 | Off  |  On  |  On  |  On  |  On  |  On  |  On  | On  |
   |-----+------+------+------+------+------+------+------+-----|
   | 255 |  On  |  On  |  On  |  On  |  On  |  On  |  On  | On  |
   |------------------------------------------------------------|
   |Note: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 on the switches and add the |
   |  values of the on switches to obtain the correct node      |
   |  address. (On=1, Off=0)                                    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                          BOOT ROM                          |
   |------------------------------------------------------------|
   |             Setting             |           JP1            |
   |---------------------------------+--------------------------|
   |>> |          Disabled           |           Open           |
   |---+-----------------------------+--------------------------|
   |   |           Enabled           |          Closed          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                         CABLE TYPE                         |
   |------------------------------------------------------------|
   |             Type              |            JP3             |
   |-------------------------------+----------------------------|
   |>> |  RG-62A/U 93ohm coaxial   |  Pins 2 & 3, 5 & 6 closed  |
   |---+---------------------------+----------------------------|
   |   |  Unshielded twisted pair  |  Pins 1 & 2, 4 & 5 closed  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     ONBOARD TERMINATOR                     |
   |------------------------------------------------------------|
   |          Setting           |              JP4              |
   |----------------------------+-------------------------------|
   |>> |        Disabled        |       Pins 2 & 3 closed       |
   |---+------------------------+-------------------------------|
   |   |        Enabled         |       Pins 1 & 2 closed       |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    INTERRUPT SELECTION                     |
   |------------------------------------------------------------|
   |            IRQ             |              JP2              |
   |----------------------------+-------------------------------|
   |            2/9             |      Pins 9 & 10 closed       |
   |----------------------------+-------------------------------|
   |             3              |       Pins 7 & 8 closed       |
   |----------------------------+-------------------------------|
   |             4              |       Pins 5 & 6 closed       |
   |----------------------------+-------------------------------|
   |             5              |       Pins 3 & 4 closed       |
   |----------------------------+-------------------------------|
   |             7              |       Pins 1 & 2 closed       |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |         BASE MEMORY ADDRESS &AMP; BOOT ROM ADDRESS         |
   |------------------------------------------------------------|
   |Base Address |Boot ROM Address|SW1/1|SW1/2|SW1/3|SW1/4|SW1/5|
   |-------------+----------------+-----+-----+-----+-----+-----|
   |    | C0000h |     C2000h     | On  | On  | On  | On  | On  |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | C4000h |     C6000h     | On  | On  | Off | On  | On  |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | CC000h |     CE000h     | On  | On  | On  | Off | On  |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |>>   | D0000h |     D2000h     | On  | On  | Off | Off | On  |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | D4000h |     D6000h     | On  | On  | On  | On  | Off |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | D8000h |     DA000h     | On  | On  | Off | On  | Off |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | DC000h |     DE000h     | On  | On  | On  | Off | On  |
   |----+--------+----------------+-----+-----+-----+-----+-----|
   |    | E0000h |     E2000h     | On  | On  | Off | Off | Off |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                      I/O BASE ADDRESS                      |
   |------------------------------------------------------------|
   |     Address     |    SW1/6     |    SW1/7    |    SW1/8    |
   |-----------------+--------------+-------------+-------------|
   |   |    260h     |      On      |     On      |     On      |
   |---+-------------+--------------+-------------+-------------|
   |   |    290h     |     Off      |     On      |     On      |
   |---+-------------+--------------+-------------+-------------|
   |>> |    2E0h     |      On      |     Off     |     On      |
   |---+-------------+--------------+-------------+-------------|
   |   |    2F0h     |     Off      |     Off     |     On      |
   |---+-------------+--------------+-------------+-------------|
   |   |    300h     |      On      |     On      |     Off     |
   |---+-------------+--------------+-------------+-------------|
   |   |    350h     |     Off      |     On      |     Off     |
   |---+-------------+--------------+-------------+-------------|
   |   |    380h     |      On      |     Off     |     Off     |
   |---+-------------+--------------+-------------+-------------|
   |   |    3E0h     |     Off      |     Off     |     Off     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DIAGNOSTIC LED(S)                      |
   |------------------------------------------------------------|
   | LED  | Color |  Status  |            Condition             |
   |------+-------+----------+----------------------------------|
   | LED1 |  Red  |   Off    |         Power is not on          |
   |------+-------+----------+----------------------------------|
   | LED1 |  Red  | Blinking |          Network error           |
   |------+-------+----------+----------------------------------|
   | LED1 |  Red  |    On    |           Power is on            |
   |------+-------+----------+----------------------------------|
   | LED2 | Green |   Off    |        Data is not being         |
   |      |       |          |       transmitted/received       |
   |------+-------+----------+----------------------------------|
   | LED2 | Green |    On    |          Data is being           |
   |      |       |          |       transmitted/received       |
   +------------------------------------------------------------+