I/O Instructions
5-15
Target Mode
Reselect Instruction
The LSI53C1000 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 LSI53C1000 wins arbitration, it attempts to reselect
the SCSI device whose ID is defined in the destination ID
field of the instruction. Once the LSI53C1000 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 LSI53C1000 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 LSI53C1000 to the initiator mode if it is reselected, or
to the target mode if it is selected.
Disconnect Instruction
The LSI53C1000 disconnects from the SCSI bus by
deasserting all SCSI signal outputs.
Wait Select Instruction
If the LSI53C1000 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
Содержание LSI53C1000
Страница 6: ...vi Preface...
Страница 16: ...xvi Contents...
Страница 28: ...1 12 Introduction...
Страница 234: ...4 124 Registers...
Страница 314: ...6 40 Specifications This page intentionally left blank...
Страница 318: ...6 44 Specifications This page intentionally left blank...
Страница 344: ...6 70 Specifications This page intentionally left blank...
Страница 350: ...6 76 Specifications Figure 6 42 LSI53C1000 329 Ball Grid Array Bottom view...
Страница 352: ...6 78 Specifications...
Страница 360: ...A 8 Register Summary...
Страница 376: ...IX 12 Index...