National Instruments GPIB-MAC User Manual page 109

November 1985
32
The CIC bit specifies whether the GPIB-MAC is the
Controller-In-Charge. The CIC bit is set whenever sic is
called while the GPIB-MAC is System Controller, or when
another Controller passes control to the GPIB-MAC. The
CIC bit is cleared whenever the GPIB-MAC detects Interface
Clear (IX) from some other device that is System
Controller, or when the GPIB-MAC passes control to
another device.
ATN 16
The ATN bit specifies the state of the GPIB Attention (ATN)
line. The ATN bit is set whenever the GPIB ATN line is
asserted and cleared when the ATN line is unasserted.
TACS 8
The TACS bit specifies whether the GPIB-MAC has been
addressed as a Talker. The TACS bit is set whenever the
GPIB-MAC detects that its talk address (and secondary
address, if enabled) has been sent either by the GPIB-MAC
itself or by another Controller. The TACS bit is cleared
whenever the GPIB-MAC detects the Untalk (UNT)
command, a talk address other than its own, its own listen
address, or Interface Clear (IX).
LACS 4
The LACS bit specifies whether the GPIB-MAC has been
addressed as a Listener. The LACS bit is set whenever the
GPIB-MAC detects that its listen address (and secondary
address, if enabled) has been sent either by the GPIB-MAC
itself or by another Controller. The LACS bit is also set
whenever the GPIB-MAC shadow handshakes as a result of
the gts function. The LACS bit is cleared whenever the
GPIB-MAC detects that the Unlisten (UNL) command, its
own talk address, Interface Clear (IX), or gts is called
without shadow handshake.
99 APPENDIX B - STATUS INFORMATION