System information

17-Nov-2014 G2T Programmers Guide Rev-A
37
5.2.2.4. BREak? command
The BREak? query is identical to the disconnect command except
that it returns an integer response:
• zero: disconnect completed
successfully
• non-zero: disconnect failed due to an
execution error or a fault.
This is a departure from other queries which do not return a
response if there was an execution error or a fault.
If the MAKe? or BREak? queries are used in a compound
command and there's an execution error or a fault, execution
continues and a response is returned. This is a departure from the
other commands which cause the rest of a compound command
to be discarded if there's an execution error or a fault.
Examples:
Connect output 1 input 1; disconnect output 1 input 2; disconnect
output 1 input 1
Connects output 1 to input 1 but when it attempts to disconnect
from output 1 input 2, the ensuing execution error stops the rest of
the command from executing and output 1 remains connected
to input 1.
Make? output 1 input 1; break? output 1 input 2; break? output 1
input 1
Return:
0,4,0
The MAKe? and BREak? queries alleviate a lot of the awkwardness
that results from attempting to implement IEEE Standard 488.2 on
serial and TCP/IP. Much of the standard is conceived around
GPIB's ability to request attention from its controller. Lacking that
ability, users of TCP/IP and serial are left with unsatisfactory
alternatives.