IEEE-488 Reference
3-87
PRINT #1, “output 27; data:fresh?”
‘ 9
PRINT #1, “enter 27”
‘ 10
LINE INPUT #2, B$
‘ 11
PRINT B$
‘ 12
END
‘
Comments:
1
Returns the Model 6517A to System Preset defaults.
2
Disables continuous initiation and places the Model 6517A in the idle state.
3, 4
Configures the Model 6517A to perform 10 measurements.
5
Disables zero check.
6, 7, 8
Takes the instrument out of idle and asserts *OPC?, which holds up execution
of subsequent GPIB commands until all 10 measurements are completed and
the Model 6517A returns to the idle state.
9, 10, 11, 12
Acquires and displays the last reading on the computer CRT. Every time the
program is run, the tenth reading will be acquired and displayed on the CRT.
3.19.4
:APERture <n>
[:SENSe[1]]:VOLTage[:DC]:APERture <n>
Set aperture for Volts
[:SENSe[1]]:CURRent[:DC]:APERture <n>
Set aperture for Amps
[:SENSe[1]]:RESistance:APERture <n>
Set aperture for Ohms
[:SENSe[1]]:CHARge:APERture <n>
Set aperture for Coulombs
Parameters
<n> =166.6666666667e-6 to 200e-3 Integration period in seconds
DEFault
Power line cycle integration:
16.67msec for 60Hz power line
20msec for 50Hz and 400Hz power line
MINimum
166.6666666667e-6sec
MAXimum
200msec
Query
:APERture?
Query programmed aperture value.
:APERture? DEFault
Query *RST default aperture value.
:APERture? MINimum
Query minimum aperture value.
:APERture? MAXimum
Query maximum aperture value.
Description
The integration period (measurement speed) for the Model 6517A can be set using either of two
commands; NPLCycle (paragraph 3.19.5) or :APERture. The NPLC method specifies the inte-
gration period as the number of power line cycles per integration, while aperture specifies the
time (in seconds) per integration. Refer to Section 2 for details on integration (SPEED). The re-
lationship between NPLC and aperture is expressed as follows:
where:
Aperture is the integration rate in seconds per integration.
NPLC is the number of power line cycles per integration.
f is the power line frequency.
For 400Hz line power, use 50Hz to calculate aperture.
Aperture =
NPLC
ƒ
