How can I use LabVIEW to output a digital signal?

[mhouston03]

I am rather new to LabVIEW and was trying to figure out how to get LabVIEW to output a digital signal from my PC-6221 DAQ card with the simple flip of a switch. I read through a previous post on the same question, and I just wanted to make sure I understand how it works fully.

So I added a new DAQ assistant to my pre-existing code and selected "Digital Output" and "Line Output". I then selected the port I wanted to use from the availble ports for the specific DAQ (For example, I selcted DIO3 for my first Boolean switch). DIO3 (accordign to a manual I have) corresponds to pin#20 on our 50 pin connector. So say for example, I have a black powder charge wired to the pin#20 on our connector, when I flip the boolean switch for that specific pin, it should send 5V to the black powder charge correct? (Our specfic DAQ outputs between 2 and 5 volts). It just seems to simple to me, and I was suspicious haha.

I attached a document of how I have the switches laid up. Currently, I have 7 switches (each set to a different port: DIO3, DIO4, etc.) to perform different tasks. So assuming the wiring is done correctly, this should work right?

Also, on a related note, I want to check for continuity for each of the swithces using LabVIEW before throwing them for safety reasons. How do I go about doing that?

THANKS!

[mhouston03]

Also, I almost forgot (and this was what I was most confused about), how do you know what boolean switch controls what? Does the switch that is wired into the first spot in the array correspond to the first item that is located in the DAQ assistant? When I open the DAQ assistant, it lists all the channels I have added, so does the first channel listed correspond to the switch in the first spot in the array? (I would include a picture to clarify, but unfortunately I am using my laptop and do not have the driver software necessary to open it)

THANKS!!!

[apok]

---

@mhouston03 wrote:

So say for example, I have a black powder charge wired to the pin#20 on our connector, when I flip the boolean switch for that specific pin, it should send 5V to the black powder charge correct? (Our specfic DAQ outputs between 2 and 5 volts). It just seems to simple to me, and I was suspicious haha.

what are you making? show us your VI......

[apok]

question:

what country are you from?

what company do you work for?

show us your VI....

sounds to me to be a major project given to someone that knows very little of LabVIEW? why cant your company spend the monies for a NI membership to get you trained? 

[AnalogKid2DigitalMan]

My guess is Cal Poly Space Systems and they are working on a hybrid rocket motor.

The ultimate in safety should be dictated in simple hardware (mechanical swiches), not in software in case of a bug, crash, or other unforeseen issue.

-AK2DM

[mhouston03]

Wow that's impressive haha. Yes I am doing this for Cal Poly Space Systems. The more I've talked with people I agree. We need to use physical switches and not LabVIEW to control the experiment. I had been for that from the start, but other individuals were somewhat pushing me to try LabVIEW. We have an old ee/control box that should work. We just need to make sure our relay box can handle the 12v outputed by the ee/control box. I believe what I have set up in LabVIEW should work though (given what I've read and seen online), but I would like to not use it if at all possible.

[apok]

---

@mhouston03 wrote:

Wow that's impressive haha. Yes I am doing this for Cal Poly Space Systems. The more I've talked with people I agree. We need to use physical switches and not LabVIEW to control the experiment. I had been for that from the start, but other individuals were somewhat pushing me to try LabVIEW. We have an old ee/control box that should work. We just need to make sure our relay box can handle the 12v outputed by the ee/control box. I believe what I have set up in LabVIEW should work though (given what I've read and seen online), but I would like to not use it if at all possible.

---

Understood....what is it that we can help you with here? I am assuming that you are an EE...

Have you looked through the NI shipped help>>Find examples on digital generation?

NI Example Finder>>Hardware Input and Output>>Daqmx>>Digital Output...

and YES!!!!! as stated, " The ultimate in safety should be dictated in simple hardware (mechanical swiches), not in software in case of a bug, crash, or other unforeseen issue."

[mhouston03]

Thanks everyone but I believe I have it figured out now. Someone else I am working with double checked what I did and it should work. Thanks though!