Avago Technologies LSI53C1000R User Manual
Page 257
I/O Instructions
5-15
Version 2.2
Copyright © 2000–2003 by LSI Logic Corporation. All rights reserved.
Target Mode
Reselect Instruction
The LSI53C1000R arbitrates for the SCSI bus by
asserting the SCSI ID stored in the
register. If it loses arbitration, it tries again during the next
available arbitration cycle without reporting any lost
arbitration status.
If the LSI53C1000R wins arbitration, it attempts to
reselect the SCSI device whose ID is defined in the
destination ID field of the instruction. When the
LSI53C1000R wins arbitration, it fetches the next
instruction from the address pointed to by the
register. This way the
SCRIPTS can move on to the next instruction before the
reselection completes. It continues executing SCRIPTS
until a SCRIPT that requires a response from the initiator
is encountered.
If the LSI53C1000R is selected or reselected before
winning arbitration, it fetches the next instruction from the
address pointed to by the 32-bit jump address field stored
in the
register. Manually set
the LSI53C1000R to the initiator mode if it is reselected,
or to the target mode if it is selected.
Disconnect Instruction
The LSI53C1000R disconnects from the SCSI bus by
deasserting all SCSI signal outputs.
Wait Select Instruction
If the LSI53C1000R is selected, it fetches the next
instruction from the address pointed to by the
register.
OPC2 OPC1 OPC0 Instruction Defined
0
0
0
Reselect
0
0
1
Disconnect
0
1
0
Wait Select
0
1
1
Set
1
0
0
Clear