Avago Technologies LSI53C825AE User Manual
Page 115
Operating Registers
4-27
register during a send operation. This byte is
combined with the first byte from the subsequent transfer
so that a wide transfer is completed.
SLPMD
SLPAR Mode
5
If this bit is clear, the
SCSI Longitudinal Parity (SLPAR)
register functions like the LSI53C825. If this bit is set, the
SLPAR register reflects the high or low byte of the SLPAR
word, depending on the state of
, bit 4. It also allows a seed value to be written
to the
SCSI Longitudinal Parity (SLPAR)
register.
SLPHBEN
SLPAR High Byte Enable
4
If this bit is clear, the low byte of the SLPAR word is
present in the
SCSI Longitudinal Parity (SLPAR)
register.
If this bit is set, the high byte of the SLPAR word is
present in the
SCSI Longitudinal Parity (SLPAR)
register.
WSS
Wide SCSI Send
3
When read, this bit returns the value of the Wide SCSI
Send (WSS) flag. Asserting this bit clears the WSS flag.
This clearing function is self-clearing.
When the WSS flag is high following a wide SCSI send
operation, the SCSI core is holding a byte of “chain” data
in the
register. This data
becomes the first low-order byte sent when married with
a high-order byte during a subsequent data send transfer.
Performing a SCSI receive operation clears this bit. Also,
performing any nonwide transfer clears this bit.
VUE0
Vendor Unique Enhancements, Bit 0
2
This bit is a read only value indicating whether the group
code field in the SCSI instruction is standard or vendor
unique. If cleared, the bit indicates standard group codes;
if set, the bit indicates vendor unique group codes. The
value in this bit is reloaded at the beginning of all
asynchronous target receives. The default for this bit is
reset.
VUE1
Vendor Unique Enhancement, Bit 1
1
This bit is used to disable the automatic byte count reload
during Block Move instructions in the command phase. If
this bit is cleared, the device reloads the Block Move byte