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5.7.2 L
ISTEN
A
DDRESS
G
ROUP
(LAG)
There are 31 (0 to 30) listen addresses associated with this group. The 3 most
significant bits of the data bus are set to 001 while the 5 least significant bits are
the address of the device being told to listen.
5.7.3 U
NLISTEN
(UNL)
This command tells all bus devices to Unlisten. This is the same as Unaddressed
to Listen. (IEEE 488 command code: $3F.)
5.7.4 T
ALK
A
DDRESS
G
ROUP
(TAG)
There are 31 (0 to 30) talk addresses associated with this group. The 3 most
significant bits of the data bus are set to 010 while the 5 least significant bits
are the address of the device being told to talk.
5.7.5 U
NTALK
(UNT)
This command tells bus devices to Untalk. This is the same as Unaddressed to Talk.
(IEEE 488 command code: $5F.)
5.7.6 L
OCAL
L
OCKOUT
(LLO)
Issuing the LLO command prevents manual control of the instrument’s functions.
(IEEE 488 command code: $11.)
5.7.7 D
EVICE
C
LEAR
(DCL)
This command causes all bus devices to be initialized to a pre-defined or power-up
state. (IEEE 488 command code: $14.)
5.7.8 S
ELECTED
D
EVICE
C
LEAR
(SDC)
This causes a single device to be initialized to a pre-defined or power-up state.
(IEEE 488 command code: $04.)
5.7.9 S
ERIAL
P
OLL
D
ISABLE
(SPD)
The SPD command disables all devices from sending their Serial Poll status byte.
(IEEE 488 command code: $19.)
5.7.10 S
ERIAL
P
OLL
E
NABLE
(SPE)
A device which is Addressed to Talk will output its Serial Poll status byte after SPE
is sent and ATN is unasserted. (IEEE 488 command code: $18.)
CHAPTER 5: IEEE 488 Primer
