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NI 5421/5441 Calibration Procedure
i.
Use the DMM to measure the voltage generated by the device. This measurement is
measurement 1
, which is used in step 8.
j.
Call
niFgen_SetAttributeViInt32
to set the offset DAC value (NI-FGEN
Offset DAC Value property) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_OFFSET_DAC_VALUE
•
value
:
15000
k.
Call
niFgen_Commit
(niFgen Commit VI) to commit the attribute values to the
device using the following parameter:
•
vi
: The session handle returned from
niFgen_InitExtCal
l.
Wait 500 ms for the output to settle.
m. Use the DMM to measure the voltage generated by the device. This measurement is
measurement 2
, which is used in step 8.
8.
Call
niFgen_CalAdjustMainPathPreAmpOffset
(niFgen Cal Adjust Main Path Pre
Amp Offset VI) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
configuration
: The
Current Configuration
value for the current iteration from
Table 10
•
gainDACValues
: An array containing two elements—the two values (
2000
,
1000
)
that you set as the gain DAC in the order that you measured them
•
offsetDACValues
: An array containing two elements—the two values (
50000
,
15000
) that you set as the offset DAC in the order that you measured them
•
measuredOutputs
: An array containing three elements—the three output voltages
(
measurement 0
,
measurement 1
,
measurement 2
) that you measured in the
order that you measured them.
Adjusting the Main Analog Path Preamplifier Gain
1.
Call
niFgen_SetAttributeViInt32
to set the analog path value (NI-FGEN Analog
Path property) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"
•
attributeID
:
NIFGEN_ATTR_ANALOG_PATH
•
value
:
NIFGEN_VAL_FIXED_LOW_GAIN_ANALOG_PATH
2.
Call
niFgen_SetAttributeViReal64
to set the postamplifier attenuation (NI-FGEN
Post-Amplifier Attenuation property) using the following parameters:
•
vi
: The session handle returned from
niFgen_InitExtCal
•
channelName
:
"0"