ADVANCED MICROCOMPUTER SYSTEMS, INC.
====================================

   422/485PC-20/DB25

   Card Type               Serial card                            
   Chip Set                Unidentified                           
   Maximum Onboard Memory  N/A                                    
   I/O Options             Serial ports (2)                       
   Data Bus                16-bit ISA                             
   Floppy drives supported N/A                                    

<gopher://bitreich.org/I/th99/i/A-B/51818-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |           Function            |           Label            |
   |-------------------------------+----------------------------|
   | 37-pin serial port connector  |            CN1             |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |             SERIAL PORT ADDRESS CONFIGURATION              |
   |------------------------------------------------------------|
   | Serial port 1 | Serial |  J7/A  |  J7/B  |  J7/C  |  J7/D  |
   |               | port 2 |        |        |        |        |
   |---------------+--------+--------+--------+--------+--------|
   |>> |   COM1    |  COM2  | Closed | Closed |  Open  |  Open  |
   |   |  (3F8h)   | (2F8h) |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM2    |  COM3  |  Open  | Closed | Closed |  Open  |
   |   |  (2F8h)   | (3E8h) |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM3    |  COM4  |  Open  |  Open  | Closed | Closed |
   |   |  (3E8h)   | (2E8h) |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM1    |  N/A   | Closed |  Open  |  Open  |  Open  |
   |   |  (3F8h)   |        |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM2    |  N/A   |  Open  | Closed |  Open  |  Open  |
   |   |  (2F8h)   |        |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM3    |  N/A   |  Open  |  Open  | Closed |  Open  |
   |   |  (3E8h)   |        |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   |   COM4    |  N/A   |  Open  |  Open  |  Open  | Closed |
   |   |  (2E8h)   |        |        |        |        |        |
   |---+-----------+--------+--------+--------+--------+--------|
   |   | Disabled  |  Open  |  Open  |  Open  |  Open  |  Open  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |             SERIAL PORT 1 INTERRUPT SELECTION              |
   |------------------------------------------------------------|
   |  IRQ  | SP1/A  | SP1/B  | SP1/C  | SP1/D  | SP1/E  | SP1/F |
   |-------+--------+--------+--------+--------+--------+-------|
   | | 2/9 | Closed |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  3  |  Open  | Closed |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   |>>|  4  |  Open  |  Open  | Closed |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  5  |  Open  |  Open  |  Open  | Closed |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  6  |  Open  |  Open  |  Open  |  Open  | Closed | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  7  |  Open  |  Open  |  Open  |  Open  |  Open  |Closed |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 10  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 11  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 12  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 14  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 15  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |         SERIAL PORT 1 INTERRUPT SELECTION (CON'T)          |
   |------------------------------------------------------------|
   |   IRQ    |  SP1/G  |  SP1/H  |  SP1/I  |  SP1/J  |  SP1/K  |
   |----------+---------+---------+---------+---------+---------|
   |   | 2/9  |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  3   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |>> |  4   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  5   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  6   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  7   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  10  | Closed  |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  11  |  Open   | Closed  |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  12  |  Open   |  Open   | Closed  |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  14  |  Open   |  Open   |  Open   | Closed  |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  15  |  Open   |  Open   |  Open   |  Open   | Closed  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |             SERIAL PORT 2 INTERRUPT SELECTION              |
   |------------------------------------------------------------|
   |  IRQ  | SP2/A  | SP2/B  | SP2/C  | SP2/D  | SP2/E  | SP2/F |
   |-------+--------+--------+--------+--------+--------+-------|
   | | 2/9 | Closed |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   |>>|  3  |  Open  | Closed |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  4  |  Open  |  Open  | Closed |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  5  |  Open  |  Open  |  Open  | Closed |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  6  |  Open  |  Open  |  Open  |  Open  | Closed | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | |  7  |  Open  |  Open  |  Open  |  Open  |  Open  |Closed |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 10  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 11  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 12  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 14  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   |-+-----+--------+--------+--------+--------+--------+-------|
   | | 15  |  Open  |  Open  |  Open  |  Open  |  Open  | Open  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |         SERIAL PORT 2 INTERRUPT SELECTION (CON'T)          |
   |------------------------------------------------------------|
   |   IRQ    |  SP2/G  |  SP2/H  |  SP2/I  |  SP2/J  |  SP2/K  |
   |----------+---------+---------+---------+---------+---------|
   |   | 2/9  |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |>> |  3   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  4   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  5   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  6   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  7   |  Open   |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  10  | Closed  |  Open   |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  11  |  Open   | Closed  |  Open   |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  12  |  Open   |  Open   | Closed  |  Open   |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  14  |  Open   |  Open   |  Open   | Closed  |  Open   |
   |---+------+---------+---------+---------+---------+---------|
   |   |  15  |  Open   |  Open   |  Open   |  Open   | Closed  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                MISCELLANEOUS TECHNICAL NOTE                |
   |------------------------------------------------------------|
   |      Note: CN1 is a DB-37 connector which has two DB-25    |
   |      (port 1 & 2) serial ports connected.                  |
   +------------------------------------------------------------+