LSI 53C875A Computer Hardware User Manual


 
SCSI Registers 4-73
Registers:0x3C–0x3F
Adder Sum Output (ADDER)
Read Only
ADDER Adder Sum Output [31:0]
This register contains the output of the internal adder,
and is used primarily for test purposes. The power-up
value for this register is indeterminate. It is used to
determine if the correct memory address was calculated
for a relative jump SCRIPTS instruction.
Register: 0x40
SCSI Interrupt Enable Zero (SIEN0)
Read/Write
This register contains the interrupt mask bits corresponding to the
interrupting conditions described in the SCSI Interrupt Status Zero
(SIST0) register. An interrupt is masked by clearing the appropriate mask
bit. For more information on interrupts, see Chapter 2, “Functional
Description.”
M/A SCSI Phase Mismatch - Initiator Mode; 7
SCSI ATN Condition - Target Mode
In the initiator mode, this bit is set when the SCSI phase
asserted by the target and sampled during SREQ/ does
not match the expected phase in the SCSI Output Control
Latch (SOCL) register. This expected phase is
automatically written by SCSI SCRIPTS. In target mode,
this bit is set when the initiator asserts SATN/. See the
Disable Halt on Parity Error or SATN/ Condition bit in the
SCSI Control One (SCNTL1) register for more
information on when this status is actually raised.
31 0
ADDER
00000000000000000000000000000000
76543210
M/A CMP SEL RSL SGE UDC RST PAR
00000000