Continuous Pattern Input time by internal clockin LabVIEW

[michael6655321]

We have a multiplexer board with 8 ports plexing down to one port that goes to a 6534. The multiplexer is timed off the 6534 internal clock. We need to make the card bring in data only when one of the lines is hot, and at the same time only look at the lines inbetween clock ticks. So far we've been able to bring in data at every tick, we are having difficulty making the board take in data on only those ticks with hot lines. Can anyone point us in the right direction? We've been using the LabVIEW 7.1 example entitled "Continuous Handshaking Input"

[Otis]

Hi Michael,

It sounds like the handshaking would be the right route for you to take to do what you are trying to have done.

You may want to take a look at some of these links to help give you a bit more information about how handshaking works with our devices:
How Do I Configure the Handshaking Lines of a 653X Board?
Line Directions with Handshaking and Pattern I/O
What are the Clock Frequencies I Can Select for Burst Mode Handshaking on a 653x Device?

You may also want to check out the example Handshaking Input-8255.vi ( NI Example Finder > Browse > Hardware Input & Output > Digital Handshaking) to see if you still get similar behavior.

Regards,

[michael6655321]

Is it possible to do handshaking and pattern recognition at the same time? The multiplexer shifts from port to port based on the pulse coming from the REQ1 pin. We are indeed so far able to take in data using handshaking. Now we need it to read in only those cycles that have activity on one or more lines.

[LYu]

Hi michael6655321,

I'm assuming you're referring to setting the same port for both handshaking and change detection (pattern recognition?), is that correct? If my understanding is correct, that's not a possible option. However, the 6534 has two groups of control lines that will allow you to configure two ports for different operations. Would it be possible to configure one port to control the multiplexer, and use the second port to latch the data upon a change?

Thanks,
Lesley