LSI 53C875A User Manual
3-8
Signal Descriptions
3.3.6 Interrupt Signal
describes the Interrupt signal.
3.4 SCSI Bus Interface Signals
The SCSI Bus Interface signals section contains tables describing the
signals for the following signal groups:
signals for the following signal groups:
,
, and
3.4.1 SCSI Bus Interface Signal
describes the SCSI Bus Interface signal.
Table 3.7
Interrupt Signal
Name PQFP BGA
Type
Strength
Description
IRQ/
52
M5
O
8 mA PCI Interrupt Request. This signal, when asserted LOW,
indicates that an interrupting condition has occurred and
that service is required from the host CPU. The output
drive of this pin is open drain.
that service is required from the host CPU. The output
drive of this pin is open drain.
1. See Register 0x4D,
in
for additional information on this signal.
Table 3.8
SCSI Bus Interface Signal
Name
PQFP
BGA
Type
Strength
Description
SCLK
56
M6
I
N/A
SCSI Clock is used to derive all SCSI-related timings. The
speed of this clock is determined by the application’s
requirements. In some applications, SCLK may be sourced
internally from the PCI bus clock (CLK). If SCLK is
internally sourced, then the SCLK pin should be tied low.
speed of this clock is determined by the application’s
requirements. In some applications, SCLK may be sourced
internally from the PCI bus clock (CLK). If SCLK is
internally sourced, then the SCLK pin should be tied low.