DECISION COMPUTER INTERNATIONAL CO., LTD.
=========================================

   MULTI 8255/8253 CARD

   Card Type         Data acquisition                             
   Chip Set          NEC 8253, 8255                               
   I/O Options       Digital I/O ports (4), counter port          
   Data Bus          8-bit ISA                                    

<gopher://bitreich.org/I/th99/i/C-D/52601-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |       Function        | Label |      Function      | Label |
   |-----------------------+-------+--------------------+-------|
   | Digital I/O port 1    |  CN1  | 8255 chip for port |  U3   |
   | (see pinout below)    |       | 4 (channel 7)      |       |
   |-----------------------+-------+--------------------+-------|
   | Digital I/O port 2    |  CN2  | 8255 chip for port |  U4   |
   | (see pinout below)    |       | 4 (channel 8)      |       |
   |-----------------------+-------+--------------------+-------|
   | Digital I/O port 3    |  CN3  | 8255 chip for port |  U6   |
   | (see pinout below)    |       | 1 (channel 1)      |       |
   |-----------------------+-------+--------------------+-------|
   | Digital I/O port 4    |  CN4  | 8255 chip for port |  U7   |
   | (see pinout below)    |       | 1 (channel 2)      |       |
   |-----------------------+-------+--------------------+-------|
   | 8253 counter port     |  CN5  | 8255 chip for port |  U8   |
   | (see pinout below)    |       | 2 (channel 3)      |       |
   |-----------------------+-------+--------------------+-------|
   | 8255 chip for port 3  |  U1   | 8255 chip for port |  U9   |
   | (channel 5)           |       | 2 (channel 4)      |       |
   |-----------------------+-------+--------------------+-------|
   | 8255 chip for port 3  |  U2   |                    |       |
   | (channel 6)           |       |                    |       |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                       CN1-CN4 PINOUT                       |
   |------------------------------------------------------------|
   |       Function        | Pin  |       Function       | Pin  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 0      |  1   | Channel 1C bit 2     |  19  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 1      |  2   | Channel 1C bit 3     |  20  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 2      |  3   | Channel 1C bit 4     |  21  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 3      |  4   | Channel 1C bit 5     |  22  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 4      |  5   | Channel 1C bit 6     |  23  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 5      |  6   | Channel 1C bit 7     |  24  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 6      |  7   | Ground               |  25  |
   |-----------------------+------+----------------------+------|
   | Channel 1A bit 7      |  8   | Ground               |  26  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 0      |  9   | Channel 2A bit 0     |  27  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 1      |  10  | Channel 2A bit 1     |  28  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 2      |  11  | Channel 2A bit 2     |  29  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 3      |  12  | Channel 2A bit 3     |  30  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 4      |  13  | Channel 2A bit 4     |  31  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 5      |  14  | Channel 2A bit 5     |  32  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 6      |  15  | Channel 2A bit 6     |  33  |
   |-----------------------+------+----------------------+------|
   | Channel 1B bit 7      |  16  | Channel 2A bit 7     |  34  |
   |-----------------------+------+----------------------+------|
   | Channel 1C bit 0      |  17  | Channel 2B bit 0     |  35  |
   |-----------------------+------+----------------------+------|
   | Channel 1C bit 1      |  18  | Channel 2B bit 1     |  36  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   CN1-CN4 PINOUT (CON'T)                   |
   |------------------------------------------------------------|
   |      Function       |  Pin   |      Function       |  Pin  |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 2    |   37   | Channel 2C bit 1    |  44   |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 3    |   38   | Channel 2C bit 2    |  45   |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 4    |   39   | Channel 2C bit 3    |  46   |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 5    |   40   | Channel 2C bit 4    |  47   |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 6    |   41   | Channel 2C bit 5    |  48   |
   |---------------------+--------+---------------------+-------|
   | Channel 2B bit 7    |   42   | Channel 2C bit 6    |  49   |
   |---------------------+--------+---------------------+-------|
   | Channel 2C bit 0    |   43   | Channel 2C bit 7    |  50   |
   |------------------------------------------------------------|
   |      Note:CN2 through CN4 are wired identically to CN1.    |
   |      CN1 has the signals for channels 1 and 2. CN2 through |
   |      CN4 have the signals for channels 3 through 8,        |
   |      respectively.                                         |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                         CN5 PINOUT                         |
   |------------------------------------------------------------|
   |          Function           | Pin |     Function     | Pin |
   |-----------------------------+-----+------------------+-----|
   | Ground                      |  1  | Counter 2B clock | 18  |
   |                             |     | signal in        |     |
   |-----------------------------+-----+------------------+-----|
   | Counter 1A clock signal in  |  2  | Gate 2B signal   | 19  |
   |-----------------------------+-----+------------------+-----|
   | Gate 1A signal              |  3  | Counter 2B clock | 20  |
   |                             |     | signal out       |     |
   |-----------------------------+-----+------------------+-----|
   | Counter 1A clock signal out |  4  | Ground           | 21  |
   |-----------------------------+-----+------------------+-----|
   | Ground                      |  5  | Counter 2C clock | 22  |
   |                             |     | signal in        |     |
   |-----------------------------+-----+------------------+-----|
   | Counter 1B clock signal in  |  6  | Gate 2C signal   | 23  |
   |-----------------------------+-----+------------------+-----|
   | Gate 1B signal              |  7  | Counter 2C clock | 24  |
   |                             |     | signal out       |     |
   |-----------------------------+-----+------------------+-----|
   | Counter 1B clock signal out |  8  | Ground           | 25  |
   |-----------------------------+-----+------------------+-----|
   | Ground                      |  9  | +5V DC power     | 26  |
   |-----------------------------+-----+------------------+-----|
   | Counter 1C clock signal in  | 10  | Ground           | 27  |
   |-----------------------------+-----+------------------+-----|
   | Gate 1C signal              | 11  | -5V DC power     | 28  |
   |-----------------------------+-----+------------------+-----|
   | Counter 1C clock signal out | 12  | Ground           | 29  |
   |-----------------------------+-----+------------------+-----|
   | Ground                      | 13  | +12V DC power    | 30  |
   |-----------------------------+-----+------------------+-----|
   | Counter 2A clock signal in  | 14  | Ground           | 31  |
   |-----------------------------+-----+------------------+-----|
   | Gate 2A signal              | 15  | -12V DC power    | 32  |
   |-----------------------------+-----+------------------+-----|
   | Counter 2A clock signal out | 16  | Ground           | 33  |
   |-----------------------------+-----+------------------+-----|
   | Ground                      | 17  | Ground           | 34  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |                 Setting                 | Label | Position |
   |-----------------------------------------+-------+----------|
   |>> | Counter 1A uses internal clock      | JP1/A |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 1A uses external clock      | JP1/A |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Counter 1B uses internal clock      | JP1/B |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 1B uses external clock      | JP1/B |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Counter 1C uses internal clock      | JP1/C |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 1C uses external clock      | JP1/C |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Counter 2A uses internal clock      | JP2/A |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 2A uses external clock      | JP2/A |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Counter 2B uses internal clock      | JP2/B |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 2B uses external clock      | JP2/B |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Counter 2C uses internal clock      | JP2/C |  Closed  |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |   | Counter 2C uses external clock      | JP2/C |   Open   |
   |   | source                              |       |          |
   |---+-------------------------------------+-------+----------|
   |>> | Base I/O address set to 140h        |  JP3  |  Closed  |
   |---+-------------------------------------+-------+----------|
   |   | Base I/O address set to 100h        |  JP3  |   Open   |
   +------------------------------------------------------------+