Operating instructions

Language Dictionary
34
*OPC? Operation Complete Output Query
Type
Device Status
Description
This query causes the electronic load to place an ASCII "1" in the Output Queue when all
pending operations are completed. Pending operations are complete when:
•
All commands that were issued before an *OPC command have been executed.
•
Any change in the input level caused by these previous commands has been
completed. (Effects of slew rate have been accounted for.)
•
No pending trigger level operations are set for the single electronic load or for any
channel of the multiple electronic load.
Unlike *OPC, *OPC? prevents processing of all subsequent commands. When all
pending operations are completed, an ASCII "1" is placed in the Output Queue.
*OPC? is intended to be used at the end of a command line so that the program can then
monitor the bus for data until it receives the "1" from the Output Queue.
Do not follow a :LEV:TRIG command (CURR:TRIG, VOLT:TRIG or RES:TRIG)
with *OPC? unless TRIG:SOUR has been previously set to EXTernal, LINE or TIMer.
These are the only triggers that can be processed after *OPC? TRIG:IMM, *TRG, and
GPIB bus triggers sent after *OPC? will be prevented from executing, stopping system
operation. If this occurs, the only programmable way to restore operation is by sending the
electronic load a GPIB DCL (Device Clear) command.
Command Syntax
*OPC?
Returned Parameters
<NR1> ASCII 1 is placed in the Output Queue when the electronic load has completed
all pending operations.
Related Commands
*OPC *TRIG:SOUR *WAI
*OPT? Options Identification Query
Type
Device Status
Description
This query specifies options installed in the multiple electronic load. The query presently
is not supported and returns a zero for all electronic loads.
Query Syntax
*OPT?
Returned Parameters
0
Suffix
None
Related Commands
*IDN? *RDT?