Address Mode Register (Admr) - National Instruments Corporation GPIB-1014P User Manual

Register Bit Descriptions
Bit Mnemonic
3r TPAS
2r LA
1r TA
0r MJMN
GPIB-1014P User Manual
Description
Talker Primary Addressed State Bit
TPAS is used when the TLC is configured for extended GPIB
addressing, and, when set, indicates that the TLC has received its primary
GPIB Talk address. In Mode 3 addressing extended mode, TPAS=1
indicates that the secondary address being received as the next GPIB
command message may represent the TLC extended (secondary) GPIB
Talk address.
Listener Active Bit
LA is set whenever the TLC has been addressed or programmed as a
GPIB Listener; that is, the TLC is in the Listener Active State (LACS) or
the Listener Addressed State (LADS). The TLC can be addressed to
listen either by sending its own listen or extended listen address while it
is Controller-In-Charge (CIC) or by receiving its listen address from an
external CIC. It can also be programmed to listen using the lon bit in the

Address Mode Register (ADMR).

If the TLC is addressed to Listen, it is automatically unaddressed to Talk.
LA is cleared by pon or by issuing the Chip Reset auxiliary command.
Talker Active Bit
TA is set whenever the TLC has been addressed or programmed as the
GPIB Talker; that is, the TLC is in the Talker Active State (TACS) the
Talker Addressed State (TADS) or the Serial Poll Active State (SPAS).
The TLC can be addressed to talk either by sending its own talk or
extended talk address while it is CIC or by receiving its talk address from
an external CIC. It can also be programmed to talk using the ton bit in
the Address Mode Register (ADMR).
If the TLC is addressed to talk, it is automatically unaddressed to listen.
TA is cleared by pon or by issuing the Chip Reset auxiliary command.
Major-Minor Bit
The MJMN bit is used to determine whether the information in the other
ADSR bits applies to the TLC major or minor Talker/Listener function.
MJMN is set to 1 when the TLC GPIB minor Talk address or minor
Listen address is received. MJMN is cleared on receipt of the TLC major
Talk or major Listen address.
Note: Only one Talker/Listener can be active at any one time. Thus, the
MJMN bit indicates which, if either, of the TLC Talker/Listener
functions is addressed or active. MJMN is always zero unless a
dual primary addressing mode (Mode 1 or Mode 3) is enabled
(see Address Mode Register later in this section).
4-22
Section Four
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