SCIENTIFIC MICROSYSTEMS, INC.
=============================

   OMTI 3520A, OMTI 3527A

   Maximum On-board    8KB                                        
   Memory              
   Data Bus            External                                   
   Card Size           3.5 in. form factor                        
   Hard Drives         Two ST-506/412(MFM) drives on OMTI 3520A   
   supported                                                      
                       Two ST-506/412(2,7 RLL) drives on OMTI     
                       3527A                                      
   Floppy drives       None                                       
   supported           

<gopher://bitreich.org/I/th99/c/S-T/21075-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |     Function     | Location |     Function      | Location |
   |------------------+----------+-------------------+----------|
   | 50-pin SCSI      |    J1    | 20-pin data cable |    J3    |
   | connector -      |          | connector - drive |          |
   | external         |          | 1                 |          |
   |------------------+----------+-------------------+----------|
   | 34-pin cable     |    J2    | 20-pin data cable |    J4    |
   | connector - hard |          | connector - drive |          |
   | drive            |          | 2                 |          |
   |------------------------------------------------------------|
   | Note: J1 is the interface between the host computer and    |
   | the OMTI 3520A/3527A. See Miscellaneous                    |
   |                                                            |
   | Technical Note.                                            |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |              Function               | Label |   Position   |
   |-------------------------------------+-------+--------------|
   |>> | SCSI parity check enabled       |  W4   |    Closed    |
   |---+---------------------------------+-------+--------------|
   |   | SCSI parity check disabled      |  W4   |     Open     |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W5   | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W6   | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W7   | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W8   | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W9   | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W10  | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W11  | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W12  | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W13  | Unidentified |
   |   | alter                           |       |              |
   |---+---------------------------------+-------+--------------|
   |>> | Termination power from board    |  W14  |  Pins 1 & 2  |
   |   |                                 |       |    closed    |
   |---+---------------------------------+-------+--------------|
   |   | Termination power from SCSI bus |  W14  |  Pins 2 & 3  |
   |   |                                 |       |    closed    |
   |---+---------------------------------+-------+--------------|
   |>> | Factory configured - do not     |  W15  | Unidentified |
   |   | alter                           |       |              |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     SCSI ID SELECTION                      |
   |------------------------------------------------------------|
   |     Setting      |     W1      |     W2      |     W3      |
   |------------------+-------------+-------------+-------------|
   |>>  |      0      |    Open     |    Open     |    Open     |
   |----+-------------+-------------+-------------+-------------|
   |    |      1      |   Closed    |    Open     |    Open     |
   |----+-------------+-------------+-------------+-------------|
   |    |      2      |    Open     |   Closed    |    Open     |
   |----+-------------+-------------+-------------+-------------|
   |    |      3      |   Closed    |   Closed    |    Open     |
   |----+-------------+-------------+-------------+-------------|
   |    |      4      |    Open     |    Open     |   Closed    |
   |----+-------------+-------------+-------------+-------------|
   |    |      5      |   Closed    |    Open     |   Closed    |
   |----+-------------+-------------+-------------+-------------|
   |    |      6      |    Open     |   Closed    |   Closed    |
   |----+-------------+-------------+-------------+-------------|
   |    |      7      |   Closed    |   Closed    |   Closed    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                MISCELLANEOUS TECHNICAL NOTE                |
   |------------------------------------------------------------|
   | Note: The OMTI 3520A and OMTI 3527A controllers are        |
   | connected to the host system via the SCSI bus              |
   |                                                            |
   | (connector J1). Up to seven SCSI devices may be connected  |
   | to this bus and an OMTI                                    |
   |                                                            |
   | 3520A/3527A controller is considered to be one of these    |
   | devices. Multliple controllers may be                      |
   |                                                            |
   | attached, with each controller assigned a unique SCSI ID   |
   | using jumpers W1, W2 and W3.                               |
   +------------------------------------------------------------+