LSI LSI53C1000, Technical Manual

Page: 203 / 384

SCSI Registers 4-93
receiving data using programmed I/O. This register can
also be used for diagnostic testing or in the low level
mode. The power-up value of this register is
indeterminate.
If the chip is in wide mode ( SCSI Control Three
(SCNTL3) , bit 3 is set) and SCSI Bus Data Lines (SBDL)
register is read, both byte lanes are checked for parity
regardless of phase. When in a nondata phase, this will
cause a parity error interrupt to be generated because
the upper byte lane parity is invalid.
Register: 0x5A
Chip Control Two (CCNTL2)
Read/Write
ShSGE Enable Shadowed SGE Register 7
Setting this bit allows access to the SGE Status registers
shadowed behind SIST0 and SIST1.
R Reserved [6:0]
Register: 0x5B
Chip Control Three (CCNTL3)
Read/Write
R Reserved [7:5]
ENDSKEW Enable REQ/ACK to Data Skew Control 4
Setting this bit enables the control of the relative skew
between the SCSI REQ/ACK signals and the data
signals. The actual amount of skew time is controlled by
DSKEW[1:0] in this register.
7 6 0
ShSGE R
0 x x x x x x x
7 5 4 3 2 1 0
R ENDSKEW DSKEW[1:0] LVDDL[1:0]
0 0 0 0 0 0 0 0