IOtech Digital488 - Listen Address Group (LAG); Unlisten (UNL); Talk Address Group (TAG); Untalk (UNT)

Section 4 IEEE 488 Primer
4.8
4.7.2 Listen Address Group (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.
4.7.3 Unlisten (UNL)
This command tells all bus devices to Unlisten. The same as
Unaddressed to Listen. ($3F)
4.7.4 Talk Address Group (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.
4.7.5 Untalk (UNT)
This command tells bus devices to Untalk. The same as Unaddressed to
Talk. ($5F)
4.7.6 Local Lockout (LLO)
Issuing the
LLO
command prevents manual control of the instrument's
functions. ($11)
4.7.7 Device Clear (DCL)
This command causes all bus devices to be initialized to a
pre-defined or power up state. ($14)