Multifunction DAQ
Arbitrary digital pulse waveform generation using PCIe-6259
Hi Jerry,
To generate the digital pulse train you describe of different pulse widths you will need to another program such as the Digital Waveform Editor to specify and generate these waveforms. The evaluation copy of the Digital Waveform editor can be downloaded from our website here. There a are a few things that you will need to do in order to get this working. The first thing that you will need to do is create a .hws file with the Digital Waveform Editor. This will allow you to control exactly how you want your digital signal to look (including setting the pulse width). Here is a picture of the signal that I made to test this out.
After saving the .hws file, you will need to load it into LabVIEW SignalExpress. This can be done by going to Add Step » Load / Save Signals » Digital Signals » Load From HWS. Select the proper file path and load the .hws signal.
The next step is setting up the generation. Go to Add Step » Generate Signals » DAQmx Generate » Digital Signals » Line Output (I would just start with 1 line at first). Select the proper port/line you want to use on your device. On the generation mode at the bottom, select whether you want N samples (once through the waveform) or continuous samples (where it repeats). This should automatically use the .hws file already loaded as the input. If it doesn't, you may need to select it.
The last part of setting this up is that you need to set an external clock. This can be a clock that you already have or one that you generate with a counter on the board. If you plan on using an external clock that you already have, wire it to a PFI line and select that line as your clock source under the Advanced timing tab on the digital output generation step. If you need to make an external clock, I would recommend for now just using test panels in Measurement and Automation Explorer (MAX) to generate the counter clock. If you right-click on your device in MAX, you can select test panels and go to the counter tab, select the frequency, output PFI line, and start generating the clock. Wire the output of the counter (counter 0 is PFI12 or pin 2) to the PFI line you selected as the external clock source (PFI0 is pin11).
This should get you started. Please let me know if you have any difficulty setting this up.
Message Edited by Vanessa L on 11-14-2007 07:26 PM
To generate the digital pulse train you describe of different pulse widths you will need to another program such as the Digital Waveform Editor to specify and generate these waveforms. The evaluation copy of the Digital Waveform editor can be downloaded from our website here. There a are a few things that you will need to do in order to get this working. The first thing that you will need to do is create a .hws file with the Digital Waveform Editor. This will allow you to control exactly how you want your digital signal to look (including setting the pulse width). Here is a picture of the signal that I made to test this out.
After saving the .hws file, you will need to load it into LabVIEW SignalExpress. This can be done by going to Add Step » Load / Save Signals » Digital Signals » Load From HWS. Select the proper file path and load the .hws signal.
The next step is setting up the generation. Go to Add Step » Generate Signals » DAQmx Generate » Digital Signals » Line Output (I would just start with 1 line at first). Select the proper port/line you want to use on your device. On the generation mode at the bottom, select whether you want N samples (once through the waveform) or continuous samples (where it repeats). This should automatically use the .hws file already loaded as the input. If it doesn't, you may need to select it.
The last part of setting this up is that you need to set an external clock. This can be a clock that you already have or one that you generate with a counter on the board. If you plan on using an external clock that you already have, wire it to a PFI line and select that line as your clock source under the Advanced timing tab on the digital output generation step. If you need to make an external clock, I would recommend for now just using test panels in Measurement and Automation Explorer (MAX) to generate the counter clock. If you right-click on your device in MAX, you can select test panels and go to the counter tab, select the frequency, output PFI line, and start generating the clock. Wire the output of the counter (counter 0 is PFI12 or pin 2) to the PFI line you selected as the external clock source (PFI0 is pin11).
This should get you started. Please let me know if you have any difficulty setting this up.
Message Edited by Vanessa L on 11-14-2007 07:26 PM
