Vizard directly supports a USB-based multifunction data acquisition and control device called LabJack. This can read voltages into digital values and convert digital values into voltages. This is probably the easiest solution since there is no direct support in Vizard to change the voltages on either serial (COM) or parallel ports.
LabJack multifunction data acquisition and control device:
http://www.labjack.com/labjack_u12.html
You might be able to find some libs available from the Python community that provide direct control of parallel but I don't immediately know of any.
03-01-2005, 09:37 AM
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