niSwitch_CalibrationDataRead

NI-SWITCH Functions

niSwitch_CalibrationDataRead

Specific Function

C Function Prototype

ViStatus niSwitch_CalibrationDataRead (ViSession vi, ViConstString channelName, ViInt32 calibrationField, ViReal64* calibrationData, ViInt32* calibrationDate_Year, ViInt32* calibrationDate_Month, ViInt32* calibrationDate_Day);

Purpose

Retrieves the calibration data, typically in terms of the amplifier offset, stored in the EEPROM.

Some NI switches have an amplifier that may require periodic calibrations. You can perform the necessary calibration and store the data locally on the switch module EEPROM. The calibration date is also stored in the EEPROM.

Parameters

Name Type Description
vi ViSession A particular NI-SWITCH session established with niSwitch_InitWithTopology, niSwitch_InitWithOptions, or niSwitch_init and used for all subsequent NI-SWITCH calls.

channelName ViConstString Name of the channel calibrated.

Examples of valid channel names:

ch0, com0, ab0, r1, c2, cjtemp



Refer to Devices for a complete list of valid channel names.

While niSwitch_ReadCalibrationData and niSwitch_WriteCalibrationData take a channel name, some switches only support a single calibration for all input channels. For example, the NI PXI-2501 uses an optional single amplifier for channels ch0 through ch47 to decrease settling time. In these cases, writing a different value to a different channel causes the previous value to be overwritten. Therefore, reading different channels returns the same calibration data.

calibrationField ViInt32 Tells NI-SWITCH which particular calibration parameter associated with this channel to read. Valid values depend on the switch hardware.

Examples of possible values:
NISWITCH_VAL_CALIBRATION_CJS_AMP (0)
NISWITCH_VAL_CALIBRATION_CHANNEL_AMP (1)

calibrationData ViReal64 Calibration data from the EEPROM.

calibrationDate_Year ViInt32 Year the switch was last calibrated with this calibration data. For example, the date August 1, 2003 would be returned as 2003 by this parameter.

calibrationDate_Month ViInt32 Month the switch was last calibrated with this calibration data. For example, the date August 1, 2003 would be returned as 8 by this parameter.

calibrationDate_Day ViInt32 Day the switch was last calibrated with this calibration data. For example, the date August 1, 2003 would be returned as 1 by this parameter.