05-13-2014 10:28 AM
I am trying to develop a program that can deliver signals to at least 10 digital output lines. The signals require precision in the range of microseconds. I am currently trying to develop this program on the Windows operating system, however after reading several papers on the NI website I believe I may need to develop a real time operating system for this project. I am outputting these signals using the PXI 6220 DAQ board. If anyone has suggestions for how to approach this please let me know.
05-13-2014 10:43 AM
The 6220 uses software timing. And you can't count on Windows to get you the precision you want.
I would recommend looking at a RT system or possibly even a FPGA card (like the PXI-7813R).
05-13-2014 10:57 AM
If I were to develop a RTOS would I still be able to use the 6220 board?
05-13-2014 11:51 AM
I'm pretty sure the PXI version of that card will work with a LabVIEW RT system. I'm not so sure about getting an RTOS with PCI slots. But since you have the PXI version, that shouldn't be much of an issue.
05-14-2014 03:42 PM
Depending on the level of precision even RT may struggle. Either way it may be simpler just to find a card that can support t hat sort of timing.
Does this require a response to something? In which case an FPGA card might be required. If it is just a fixed pattern you could use an DAQ card that supports hardware timing or a digital card. Try this search: http://sine.ni.com/np/app/main/p/bot/no/ap/daq/lang/en/pg/1/sn/n17:daq,n36:8854,n4:7858,n35:hw/
05-15-2014 08:49 AM
For this application, we need a program that can send out the digital signals with very accurate timing precision, it does not need to respond to any input data. Essentially what I would like to do is create a custom clock pulse that will output the on or off state of around 8 channels. So for example, the first clock pulse goes high and the 8 channel states are output, then 1 microsecond later the pulse goes low and does not go high again for say 10 milliseconds, but when it does it updates the on off states of the channels. This process will repeat with varying pulse lentghs as the experiment needs. We are using a PCI 6220 digital I/O board with LV 2010 32 bit software. Any suggestions are greatly appreciated.
05-15-2014 10:14 AM
It has already been explained that software timed DIO is not really going to get you a solution.
you will need some other hardware see this list for hardware timed DIO products.
05-15-2014 10:25 AM
Or something like this might work for you as well:NI PCIe-6537B