LSI LSI53C1000, Technical Manual

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SCSI Registers 4-83
Register: 0x4D
SCSI Test One (STEST1)
Read/Write
R Reserved [7:6]
DOSGE Disable Outbound SCSI Gross Errors 5
When set, this bit disables all SCSI gross errors related
to outbound data transfers.
DISGE Disable Inbound SCSI Gross Errors 4
When set, this bit disables all SCSI gross errors related
to inbound data transfers.
QEN SCLK Quadrupler Enable 3
This bit, when set, powers up the internal clock
quadrupler circuit, which quadruples the SCLK 40 MHz
clock to the internal 160 MHz SCSI clock required for
Ultra2 and Ultra160 SCSI operation. When cleared, this
bit powers down the internal quadrupler circuit. Refer to
Chapter 2, “Functional Description,” for information
concerning the operation of the quadrupler.
QSEL SCLK Quadrupler Select 2
This bit, when set, selects the output of the internal clock
quadrupler as the internal SCSI clock. When cleared, this
bit selects the clock presented on SCLK as the internal
SCSI clock. Refer to
Chapter 2, “Functional Description,”
for information concerning the operation of the
quadrupler.
IRM[1:0] Interrupt Routing Mode [1:0]
The LSI53C1000 supports four different interrupt routing
modes. These modes are described in the following table.
Mode 0, the default mode, is compatible with RAID
upgrade products.
7 6 5 4 3 2 1 0
R DOSGE DISGE QEN QSEL IRM[1:0]
0 0 0 0 0 0 0 0