LSI LSI53C1000, Technical Manual

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5-20 SCSI SCRIPTS Instruction Set
Relative
Uses the device ID in the instruction, but treats the
alternate address as a relative jump.
Table Relative
Treats the alternate jump address as a relative jump and
fetches the device ID, synchronous offset, and
synchronous period indirectly. The value in bits [23:0] of
the first four bytes of the SCRIPTS instruction is added
to the data structure base address to form the fetch
address.
Sel Select with ATN/ 24
This bit specifies whether SATN/ is asserted during the
selection phase when the LSI53C1000 is executing a
Select instruction. When operating in the initiator mode,
set this bit for the Select instruction. If this bit is set on
any other I/O instruction, an illegal instruction interrupt is
generated.
R Reserved [23:20]
ENDID[3:0] Encoded SCSI Destination ID [19:16]
This 4-bit field specifies the destination SCSI ID for an I/O
instruction.
Command Table Offset
Absolute Alternate Address
Command ID Not Used Not Used
Absolute Jump Offset
Command Table Offset
Absolute Jump Offset