Why Can't I Tristate My NI 6509 Digital Lines?

Updated Oct 18, 2018

Reported In


  • PCI-6509

Issue Details

Why do I get Error -200077 or Error -201223 when I programmatically set my NI 6509 digital lines to tristate using the DO.Tristate property?

Figure 1: Error -200077 Setting One Line to DO.Tristate with DAQmx 8.6 or Earlier.

Figure 2: Error -201223 Setting One Line to DO.Tristate with DAQmx 8.7 or Later.


DAQmx 8.6 and Earlier
Before DAQmx 8.7 the DAQmx Channel Property DO.Tristate was used for line-by-line configuration. The NI 6509 is programmed port-by-port, which makes the use of this property incompatible, as shown by the error in Figure 1. A subVI has been created as a substitute for the property, which can be found linked below. Replace the DO.Tristate property with the subVI attached below.

DAQmx 8.7 and Newer
In DAQmx 8.7 the DO. Tristate property added support for the NI 6509 by allowing tristate by port. Since the NI 6509 can only be tristated on a port by port basis, this now allows the user to set a particular port of the NI 6509 to tristate the outputs of that port. 

You may run into the issue that is shown in Figure 2 if you try to use the DO.Tristate property if the lines in your DAQmx task do not consume the full port. For example, the error in Figure 2 was received because the Lines input to the DAQmx Create Channel VI was set to port0/line0. The error was resolved by setting the lines to port0/line0:7. 


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