Specifications
148
E.2 D/A Calibration (for PCI-1716 only)
You can select an on-board +5V or +10V internal reference voltage or
an external voltage as your analog output reference voltage. If you use
an external reference, connect the reference voltage within the ±10V
range to the reference input of the D/A output channel you want to
calibrate. Then adjust the gain value, unipolar offset voltage, bipolar
offset voltage, respectively, of D/A channels 0 and 1 with the
Calibration Command and Data register (BASE+18).
Note:
Using a precision voltmeter to calibrate the D/A outputs is recommended.
The auto-calibration program AutoCali.EXE helps you finish the D/A
calibration procedure automatically. In order to get the maximum
possible accuracy of the D/A channels, you need to calibrate the A/D
channels first. Although the procedure is not necessary, the following
calibration steps are provided below for your reference in case you
want to implement the calibration yourself:
1. Writing 0x0400, 0x0500, 0x0600, 0x0700, 0x0800, 0x0900,
0x0A00 and 0x0B00 sequentially to Calibration Command and
Data register (BASE+18). Next, to set PCI-1716/1716L to AI
software trigger and calibration mode. After that, to set the A/D
channel to corresponding D/A channel. That means connected A/D
channel 4 to D/A channel 0, connected A/D channel 6 to D/A
channel 1.
2. Adjust GAIN 10V calibration. First, writing any value to