Avago Technologies LSI53C1010 - Manual (Page 135)

Flag Fields 4-15
4.8.1 NOT
NOT negates (logically inverts) the conditions specified by the qualifiers
that follow. For example, an instruction that reads
RETURN if NOT data
compares data to the contents of the SFBR register. If they are not
identical, the operation executes. Usage:
JUMP address, if NOT data
4.8.2 AND
AND is used to compound the condition being tested. All conditions that
are added with the AND keyword must be true for the operation to
execute. Usage:
RETURN, WHEN data AND MASK DATA
4.8.3 OR
OR specifies a list of conditions, one of which must be true for the
operation to execute. Usage:
CALL REL (address), IF NOT ATN OR data
4.9 Flag Fields
The Flag Fields keywords signify that a flag field bit has been set. The
flag field bits are controlled with the SET and CLEAR instructions.
4.9.1 ACK
The target checks to see if the SCSI ACK/ signal is asserted. Usage:
CLEAR ACK
4.9.2 ATN
The target checks to see if the initiator has set the SCSI ATN/ signal.
Usage:
JUMP address, IF NOT ATN