PCI 6221 digital output

[maxva]

Hello. I have a card NI-6221 PCI with Labview 7.0 and NI DAQ. I would like to pilot 24 digital outputs simultaneously. I manage to command one port (8 outputs), but impossible to manage 3 ports in the same application. To do it I based myself on the example: Multi-Function-Synch Dig Read Write With Counter.vi. If somebody can give me explanations onto this problem I shall be grateful to him(her) for it. Thank you.

[Benjamin_C]

Hello,

You can use all 3 ports to perform static Digital I/O. Static DIO is basic digital IO that employs no handshaking or hardware-controlled timing. There is no clock associated with the functionality.

If you program involves any type of sample clock, then you are no longer performing static DIO, but correlated DIO. Correlated DIO enables digital and analog functions to be synchronized with hardware-timed precision. Basically, a clock is associated with the digital functionality. Port 0 of your M Series is the only DIO port available for correlated DIO.

If you need to clock your digital acquisition or generation on the 3 ports, then you need a High-Speed Digital I/O Device.

I hope this helps.

[maxva]

Merci Benjamin pour vos explications.