Using NI 6503 DIO

[Laurent Pueyo]

I experience the same problem as the one refered in :

http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=50650000000800000083400000&ECategory=Measurement+Hardware.Digital+I/O

But I encounter also the same kind of "coupling" betwee port. That is to say that I can't write to a port of my 6503 without resetting the two other ones. A software memory of the ports states seems useless on this case.

If someone has any idea that could be very useful.

Thanks a lot
Regards
Laurent

[Christian_L]

Laurent,

What development tool/language are you using and what function are you using to set the state of the digital lines? Example code? As stated before all the lines in one port (eight lines) will always be set together, but you should be able to set the three ports independent of each other. Are you possibly resetting all three ports as part of writing new data to one port?

To maintain the state of the other lines on the port you are changing, you will need to keep the current state of the port in a softcopy in your application and then only change the desired bits, before writing the new softcopy to the port.

Christian L
NI Consulting Services