LSI53C875 LSI Logic, LSI53C875 Datasheet - Page 143

• Manufacturer Part Number: LSI53C875
• Description: PCI to Ultra SCSI I/O Processor
• Manufacturer: LSI Logic

AIP
LOA
WOA
RST/
SDP0/
Register: 0x0E (0x8E)
SCSI Status One (SSTAT1)
Read Only
FF[3:0]
7
0
0
FF[3:0]
Arbitration in Progress
Arbitration in Progress (AIP = 1) indicates that the
LSI53C875 has detected a Bus Free condition, asserted
BSY, and asserted its SCSI ID onto the SCSI bus.
Lost Arbitration
When set, LOA indicates that the LSI53C875 has
detected a bus free condition, arbitrated for the SCSI bus,
and lost arbitration due to another SCSI device asserting
the SEL/ signal.
Won Arbitration
When set, WOA indicates that the LSI53C875 has
detected a Bus Free condition, arbitrated for the SCSI
bus and won arbitration. The arbitration mode selected in
the
arbitration and selection to set this bit.
SCSI RST/ Signal
This bit reports the current status of the SCSI RST/
signal, and the RST signal (bit 6) in the
(ISTAT)
as it is read.
SCSI SDP0/ Parity Signal
This bit represents the active high current status of the
SCSI SDP0/ parity signal. This signal is not latched and
may change as it is read.
FIFO Flags
These four bits, along with
bit 4, define the number of bytes or words that currently
reside in the LSI53C875’s SCSI synchronous data FIFO
and shown in
they will change as data moves through the FIFO.
SCSI Control Zero (SCNTL0)
0
register. This bit is not latched and may change
Table
4
0
5.5. These bits are not latched and
SDP0L
3
x
SCSI Status Two
MSG
2
x
register must be full
Interrupt Status
C/D
1
x
(SSTAT2),
I/O
0
x
[7:4]
5-27
4
3
2
1
0