ADAPTEC, INC.

ACB-4000A, ACB-4070

  Data bus:                  None (SCSI to ST506 interface)

  Size:                      Drive card

  Hard drives supported:     SCSI to two RLL ST506 drives

  Floppy drives supported:   None

[Image]

                             CONNECTIONS

                    Function                          Location

  20-pin data cable connector-drive 0                    CN0

  20-pin data cable connector-drive 1                    CN1

  34-pin control cable connector-hard drive(s)           CN2

  4-pin connector-DC power                               CN3

  50-pin SCSI connector-to host adapter                  CN4

                               SCSI ADDRESS

    SCSI ID        JP5/Jumper 1       JP5/Jumper 2        JP5/Jumper 3

         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

                        USER CONFIGURABLE SETTINGS

                Function                     Location          Setting

  »   Write precomp. disabled                   JP2           pins 1 & 2
      (ACB-4000A only)                                         closed

      Write precomp. same as R.W.C.             JP2           pins 2 & 3
      (ACB-4000A only)                                         closed

      Write precomp. to all tracks              JP2           pins 2 & 4
      enabled (ACB-4000A only)                                 closed

  »   DMA transfer rate is SYSCLOCK/4      JP5/jumper 4        closed

      DMA transfer rate is DATACLOCK/2     JP5/jumper 4         open

  »   Extended command set enable -        JP5/jumper 5        closed
      SASI compatible

      Extended command set disabled        JP5/jumper 5         open

  »   Not used                             JP5/jumper 6         open

  »   Supports the SEEK COMPLETE line      JP5/jumper 7        closed
      during head switches

      SEEK COMPLETE Cmd. not supported     JP5/jumper 7         open

  »   Self-diagnostics enabled             JP5/jumper 8        closed

      Normal operation                     JP5/jumper 8         open

                       MISCELLANEOUS TECHNICAL NOTES

      The function of JP1 is to determine the select technique used to
                        interface the host adapter.

   Soldering Pin 2 to Pin "P" allows for the "pulse" select that is used
  by controllers designed to work with SASI hosts. Soldering Pin 2 to Pin
  "H" or "L" allows for the "level" select signal used in accordance with
                              SCSI standards.