Setting FPGA data Direction

[colinowen]

Having a minor problem using FPGA 7831 Digital IO, at this stage just trying to do the FPGA equivalent of "Hello World"!!!!!

If we set one digital port:

high nibble as inputs

low nibble as outputs

And then write a value to the whole port, it appears to reconfigure the whole port as an output and ignore the data direction that has been set. Is this normal? I have some experience using a couple of micro's that if you set bits as inputs, these are ignored when doing a port write. I was expecting the FPGA ports to behave in the same way.

The obvious work around is to only write to those ports you have configured as outputs!!!

[AdamB]

Colin,

What functions are you using for your outputs?

If you have a look in the advanced FPGA Device I/O functions palette you will find the "Digital Port Data" function.
If you look up the help for this function you will see that it sends data to the port without reconfiguring the whole port as an output port.
Try using this?

Adam Bakehouse
National Instruments

[colinowen]

Thanks for the reply Adam.

After posting the question, we spotted the two different 'Write' options and sorted it. Very simple when you know!!