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2 the scsi interface, The scsi interface – LSI 21003 User Manual

Page 49

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Operational Environment

3-7

3.2.2 The SCSI Interface

The SCSI interface conforms to ANSI X3T10.11/1142.

The SCSI interface operates as two 16-bit, SE or LVD channels, and
supports Fast, Ultra, Ultra2, and Ultra160 SCSI protocols. The interface
is made through connectors J2, J3, and J4 for Channel A and J5 for
Channel B.

J2 is a 68-pin high density right-angle connector for internal SCSI
connections to Channel A. J3 is a 50-pin high density right-angle
connector that protrudes through the ISA/EISA bracket for external
connections to Channel A. Also on Channel A is connector J4, which is
a 50-pin narrow (ribbon) connector for internal connections. Channel A
has autosensing, active SE SCSI termination.

J5 is a 68-pin high density latching right-angle connector for internal
SCSI connections to Channel B. Channel B has active, SE or LVD SCSI
termination that is always enabled.

SCSI TERMPWR is supplied by the board.

Tables

3.4

,

3.5

,

3.6

, and

3.7

document the signal assignments for J2, J3,

J4 and J5 respectively.