DATA TECHNOLOGY CORPORATION
===========================

   DTC5280CL, DTC5280CRA, DTC5280CRZ

   +------------------------------------------------------------+
   +------------------------------------------------------------+

   Data bus: 16-bit, ISA

   Size: Full-length, full-height card

   Hard drives supported:  Two MFM ST506 drives

   Floppy drives supported: Two 360KB, 720KB, 1.2MB, or 1.44MB

   Sector interleave: 2:1

<gopher://bitreich.org/I/th99/c/C-D/20069-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |                 Function                  |    Location    |
   |-------------------------------------------+----------------|
   | 34-pin data cable connector-floppy drive  |       J1       |
   |-------------------------------------------+----------------|
   | 34-pin control cable connector-hard drive |       J2       |
   |-------------------------------------------+----------------|
   | 20-pin data cable connector-drive 0       |       J3       |
   |-------------------------------------------+----------------|
   | 20-pin data cable connector-drive 1       |       J4       |
   |-------------------------------------------+----------------|
   | 4-pin connector-drive active LED          |       J5       |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |               Function                | Location | Setting |
   |---------------------------------------+----------+---------|
   |>> | Auto-deselect disabled            |    W1    |  open   |
   |---+-----------------------------------+----------+---------|
   |   | Auto-deselect enabled             |    W1    | closed  |
   |---+-----------------------------------+----------+---------|
   |>> | Hard drive port addresses are     | W2 & W3  |  open   |
   |   | 1F0-1F7 3F0-3F7h                  |          |         |
   |---+-----------------------------------+----------+---------|
   |   | Hard drive port addresses are     | W2 & W3  | closed  |
   |   | 170-177 370-377h                  |          |         |
   |---+-----------------------------------+----------+---------|
   |>> | Floppy drive data transfer rate   |    W4    |  open   |
   |   | is 500KHz                         |          |         |
   |---+-----------------------------------+----------+---------|
   |   | Floppy drive data transfer rate   |    W4    | closed  |
   |   | is 250KHz                         |          |         |
   |---+-----------------------------------+----------+---------|
   |>> | Floppy drive precompensation is   |    W7    |  open   |
   |   | scaled by data rate:              |          |         |
   |   |                                   |          |         |
   |   | 500KHz=125ns, 300KHz=208ns,       |          |         |
   |   | 250KHz=250ns                      |          |         |
   |---+-----------------------------------+----------+---------|
   |   | Floppy drive precompensation is   |    W7    | closed  |
   |   | 125ns                             |          |         |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DRIVE SELECT MODE                      |
   |------------------------------------------------------------|
   |              Function               |   W5   | W6/jumper 1 |
   |                                     |        | & W6/jumper |
   |                                     |        |      2      |
   |-------------------------------------+--------+-------------|
   |>> | Firmware D.S. mode - Drv. #     | closed | pins 2 & 3  |
   |   | driven to interface             |        |   closed    |
   |---+---------------------------------+--------+-------------|
   |   | Firmware D.S. mode - Drv. #     |  open  | pins 1 & 2  |
   |   | intercepted by controller       |        |   closed    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |               MISCELLANEOUS TECHNICAL NOTES                |
   |------------------------------------------------------------|
   |  This controller has no onboard user accessible programs.  |
   +------------------------------------------------------------+