inexactly voltage with PCI-MIO-16E-4

I have measured voltage with the ADC part of a PCI-MIO-16E-4 board from
National Instruments. The voltage source is calibrated.
I have the following result:

voltage source  /  measured with PCI-MIO-16E-4
9V  /  9,165
6V  /  6,11
4V  /  4,0755
2V  /  2,039
0V  /  0,049

Must I calibrate the board?

I have found the following description (National Instruments user manual)
about the calibration:

"The associated calibration constants-the values that were written to the
CalDACs to
achieve calibration in the factory-are stored in the onboard nonvolatile
memory (EEPROM). Because the CalDACs have no memory capability,
they do not retain calibration information when the device is unpowered.
Loading calibration constants refers to the process of loading the CalDACs
with the values stored in the EEPROM. NI-DAQ software determines
when this is necessary and does it automatically. If you are not using
NI-DAQ, you must load these values yourself."

How I can load the values with comedi?

Markus Dostal

Received on 2002-09-24Z06:17:15