Hi! I am trying to generate a Manchester code through a digital output of the PXIe-6612 module. In the attached VI, I am able to generate a Manchester code over 1ms clock. This means that as each bit is encoded in a low-to-high or high-to-low transition, each bit actually takes 2ms to transmit. The thing is that I have to generate the signal with a period of 500us --> I would need to execute the loop every 250us. Which is the best way to do this? I am a newbie in LabView. Any assistance would be appreciated.

Lucky you, your device is a newer design that can derive its own sample clock for DO tasks. So if you're working on a modified version of the shipping example, you can just select "OnboardClock" and DAQmx will figure out the rest for you. (The same would be true if you simply left the corresponding input on DAQmx Timing.vi unwired. That would tell DAQmx to do the default thing, which is to derive a sample clock from its internal timebase.) -Kevin P

You will need to create a digital waveform task and output that through the DIO board. This takes the timing away from your software (which will be slow) and puts it on your board (which is actually made for this). Open the example finder (Help->Find Examples) and go to Hardware Input and Output->DAQmx->Digital Output->Digital - Finite Output.vi. That example should be what you are looking to do.

Digital I/O

Manchester Bits generation

Solved!

Author

Never mind. I changed the port from P0.14 to P0.0 and now I see the signal in the oscilloscope. For some reason, the vi doesn't work with output P0.14.

Message 11 of 11

(347 Views)

Digital I/O

Manchester Bits generation

Re: Manchester Bits generation