SCIENTIFIC MICRO SYSTEMS

OMTI 5520, OMTI 5527

Data bus: 8-bit, ISA

Size: Half-length, full height card

Hard drives supported: OMTI 5520:Two MFM ST506/ST412 drives

OMTI 5527:Two RLL ST506/ST412 drives

Floppy drives supported: None

Maximum heads/cyl.: 16 heads and 2048 cylinders

[Image]

                           CONNECTIONS

                  Function                        Location

  34-pin control cable connector-hard drive          CN1

  20-pin data cable connector-drive 0                CN2

  20-pin data cable connector-drive 1                CN3

  6-pin DC power connector                           J4

                        USER CONFIGURABLE SETTINGS

              Function                     Location           Setting

  »   BIOS enabled                            W7                open

      BIOS disabled                           W7               closed

  »   BIOS base address is C8000h             W8                open

      BIOS base address is CA000h             W8               closed

  »   Drive 0 soft sectored                   W11               open

      Drive 0 hard sectored                   W11              closed

  »   Drive 1 soft sectored                   W14               open

      Drive 1 hard sectored                   W14              closed

      Not used                                WP9

      Drive 0 is a removable drive            W10              closed
      ;drive 1 is a fixed drive
                                              W11               open
      (OMTI 5527 only,JP10-11 are
      not used on the 5520)

      Drive 0 & 1 are both hard               W10               open
      sectored
                                              W11              closed
      (OMTI 5527 only, JP10-11 are
      not used on the OMTI 5520.)

  »   Factory configured - do not             W12               N/A
      alter

  »   Not documented                      W17,19,20,            N/A

                                          27,28,29,30

                             I/O PORT ADDRESS

          Address                 Jumper W5               Jumper W6

  »          320h                   open                    open

             324h                  closed                   open

             328h                   open                   closed

             32Ch                  closed                  closed

                       MISCELLANEOUS TECHNICAL NOTES

  W1 through W4 are used to configured the drive type as supported by the
    BIOS. To support most of the drives on the market, there are several
     different BIOS’s offered. The different BIOS drive type tables are
   listed with the OMTI 5510; The settings are the same for the 5520 and
                                 the 5527