National Instruments GPIB-MAC User Manual page 74

November 1985
rsc - Request or Release System Control
Initialization function
Syntax:
Purpose: You use rsc if some other device in your GPIB system
should be System Controller.
Remarks: If the argument
itself to be the GPIB System Controller. If the argument
System Controller.
If you call rsc without an argument, the GPIB-MAC
returns to you its System Controller status, which is 0 if
GPIB-MAC is not currently System Controller or 1 if the
GPIB-MAC is System Controller.
As System Controller the GPIB-MAC can send the Inter-
face Clear (IX) and Remote Enable @EN) messages to
GPIB devices. If some other Controller asserts Interface
Clear, the GPIB-MAC cannot respond unless it is
configured as not System Controller.
In most applications, the GPIB-MAC will be System
Controller. In some applications, the GPIB-MAC will
never be System Controller. In either case,
used only if the Macintosh is not going to be System
Controller while the program executes. The IEEE-488
standard does not specifically allow schemes in which
System Control can be passed from one device to an-
other, however,
The GPIB-MAC configures itself to be System Control-
ler at power-on.
Refer also to
SECTION FOUR - FUNCTIONS
63
is 0, the GPIB-MAC configures itself as not
rsc
sic
and
is 1, the GPIB-MAC configures
could be used in such a scheme.
sre.
rsc
is