6711 dio

[lmtis]

Hi all,
I am trying to use an NI PCI-6711 card for DIO.  I am trying to drive stepper motors using the DIO single read/write VI.  I can write to the first 6 ports with MAX just fine.  Using the DIO single read/write I can write to DIO0 with no problem, but I cannot figure out how to address the remaining ports.  What am I missing?

[BrowningG]

Hello Jim,

Thanks for contacting National Instruments. 

According to the LabVIEW help file information regarding the DIO Single Read/Write VI, there are two options for the digital channel list input.  The first uses a list of configured digital channel names using any virtual channels configured in Measurement and Automation Explorer.  The second uses a list of digital ports on the device and would actually use the port numbers for the device.  By using the actual port numbers in the list, all of the digital lines in the port are configured at once.  According to the PCI 6711 specifications sheet, this device has only one DIO port.  So by specifying DIO0, you have included all eight digital lines for the device.  The updates to write input for this VI requires that each element of updates to write should be a bit pattern representing the lines of the port. 

Also, since it seems you are starting a new project, it could be beneficial to use the NI DAQmx driver.  One of the benefits to this driver is the fact that the channel controls and constants will auto-populate with appropriate inputs for each task.  The resource Transition from Traditional NI-DAQ to NI-DAQmx in LabVIEW provides good information on upgrading existing applications to the DAQmx driver.  The DAQmx shipping example Write Dig Chan is quite similar to the test panels in MAX and would be a good place to start if you do decide to switch to DAQmx.

 Please post back if you have any questions.