Konica Minolta PCI-1712L user manual 6.3 D/A Calibration

Chapter 6

mode. Adjust the gain until the AI0’s value converges between 0 and 1.

7.Repeat steps 4 to 6 several times.

6.3D/A Calibration

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 associ- ated register (BASE+2C).

Note:

✎A precision voltmeter is recommended to calibrate the D/A outputs.

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.Calibrate the A/D channels first.

2.Set PCI-1712 in calibration mode. AI4 is connected to AO0 and AI6 is connected to AO1. (Write “1” to the bit, AIO_CAL, on register BASE+6 bit7)

3.Set the unipolar output range of both AO0 and AO1 the same as the internal or external reference voltage range, either 0 to 5V or 0 to 10 V.

4.Set the output value of the AOn (where n=0 or 1) data register at (BASE+0x0C) as 0x0ffe and output to AOn.

5.Adjust the associated gain register (BASE+0x0C) until the AOn output value reads AI4+2n equals 0x0ffe.

6.Set the output value of the AOn data register (BASE+0x0C) as 0x0001 and output to AOn.

7.Adjust the associated unipolar offset register (BASE+0x2C) until

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