Table 3.11 scsi function a signals, Scsi function a signals – Avago Technologies LSI53C896 User Manual
Page 102

3-14
Signal Descriptions
Version 3.3
Copyright © 1998–2003 by LSI Logic Corporation. All rights reserved.
describes the signals for the SCSI Function A Signals group.
Table 3.11
SCSI Function A Signals
Name
Bump
Type
Strength
Description
A_SD[15:0]
−
A_SDP[1:0]
−
B5, C5, B4, C4,
D19, A19, D18,
A18, D11, A9, D9,
A8, D8, A7, C7, B6
C6, A10.
I/O
48 mA
SCSI
SCSI Function A Data and Parity.
LVD Mode: Negative half of LVDlink pair for
SCSI data and parity lines. A_SD[15:0]
−
are the 16-bit SCSI data bus, and
A_SDP[1:0]
−
are the SCSI data parity lines.
SE Mode: A_SD[15:0]
−
are the 16-bit
SCSI data bus, and A_SDP[1:0]
−
are the
SCSI data parity lines.
HVD Mode: A_SD[15:0]
−
and A_SDP[1:0]
−
are the SCSI data bus.
A_SD[15:0]+
A_SDP[1:0]+
A5, D5, A4, A3,
C19, B19, C18,
B18, B10, C10, B9,
C9, B8, C8, B7, A6
D6, C11
I/O
48 mA
SCSI
SCSI Function A Data and Parity.
LVD Mode: Positive half of LVDlink pair for
SCSI data lines. A_SD[15:0]+ are the
16-bit data bus, and A_SDP[1:0]+ are the
SCSI data parity lines.
SE Mode: A_SD[15:0]+ and A_SDP[1:0]+
are at 0 V.
HVD mode: A_SD[15:0]+ and A_SDP+ are
driver directional control for SCSI data lines.
A_DIFFSENS
A20
I
N/A
SCSI Function A Differential Sense pin
detects the present mode of the SCSI bus
when connected to the DIFFSENS signal
on the physical SCSI bus.
LVD Mode: When a voltage between 0.7 V
and 1.9 V is present on this pin, the SCSI
Function A operates in the LVD mode.
SE Mode: When this pin is driven LOW
(below 0.5 V) indicating SE bus operation,
the SCSI Function A operates in the
SE mode.
HVD Mode: When this pin is detected HIGH
(above 2.4 V) indicating an HVD bus, the
SCSI Function A 3-states its SCSI drivers.
Set the DIF bit in
to enable HVD drivers.