System information

G2T Programmers Guide Rev-A 17-Nov-2014
56
• Query Error (QYE, weight 4)
It indicates that the device was addressed to talk when the
output queue was empty or that a new command was
received before the output queue was emptied. Both
cases are possible under GPIB, but highly unlikely with other
interfaces.
•
Request Control (RQC, weight 2)
It is not used and always clear.
•
Operation Complete (OPC, weight 1)
Execution of the *OPC common command causes this bit
to be immediately set. See the description of the *OPC,
*OPC? And *WAI commands for details.
A command error (CME) results from the processor encountering a
syntax error in a command. If the command is a compound
command, all commands up to the offending command are still
scheduled to execute. The command with the error and any
following commands are discarded.
As indicated previously, the CME bit of ESR is set. Additionally, a
numeric code is placed in the Last Command Error register (see
below) to indicate the nature of the syntax error.
An execution error (EXE) results from the processor attempting to
execute an otherwise syntactically correct command that violates
some condition. Some examples might be an output that’s out of
range or trying to connect to an output that’s already in use when
auto-interlock is not activated. Again, if it’s a compound
command, all commands up to the offending command are
executed.
The command with the execution error and any commands
following it are discarded. Again, the EXE bit of ESR is set and a
numeric code is placed in the Last Execution Error register (see
below).
A query error (QYE) sets the QYE bit of the ESR and causes a
numeric code to be entered in the Last Query Error register (see
below). It does not affect the parsing or execution of otherwise
valid commands except to indicate that valid responses may
have been lost.