Laser Transmitter & Receiver

[briantan]

Hi and Good Day to All

I am a hobby-ist in Singapre and would like to do an mini project where I need to link my pc to my laser transmitter & Receiver. The transmitter is constantly transmitting the laser pulse/signal. When this constant is not interrupted, the receiver (detector) sends an OK signal to a possible Man-machine interface (MIMI). If interrupted, the receiver will feedback to the MIMI, which in turns will triggers an alarm/siren, etc....

I am using Labview Student Edition, Windows XP Pro, and thinking of using a basic USB interface adpater from NI to make this security alarm system possible.

I am really stuck despite going thru various examples in the net and my Student edition software. If someone can knock up a simple VI or point me in the correct direction, I would be eternally grateful.

Very Much Thanks

Brian

[JLS]

Hello,

I think I can help you, however, we'll need to clarify some things.  First, I presume that your MMI is your "USB device" and your receiver is really your computer with a USB port.  If this is the case, you can use LabVIEW and NI-VISA on the receiver (computer) side to communicate with your MMI.  There are really two cases to consider:

1. your MMI is a USBTMC compatible device - in this case you will be able to use the open, write, read, close portion of the VISA API in order to communicate with the MMI; in this case the MMI will have a string command API documented, where you'll be able to use the VISA Write function to write string commands to control it, and the VISA Read function to receive messages from it. 

2. your MMI is NOT a USBTMC compatible device - in this case you will eventually use the general open, write, read, close VISA API, along with some USB specific VISA functions in order to communicate with your device in a more fundamental/rudimentary way.  In this case, you'll have to tell the operating system to make NI-VISA the driver for your MMI; you do this with the VISA Driver Development Wizard which writes and optionally installs a so-called INF file defining NI-VISA as the driver for your MMI. After running the wizard, your device will show up in Measurement and Automation Explorer and in VISA Resource Controls and Constants in LabVIEW as a VISA resource.

NOTE: in case 2 you'll have to know almost everything about how your USB device accepts data; you'll need to know the precise binary data to write to it in order to control it.

Here are links to tutorials, knowledge base documents, and examples which you should definitely study if you are indeed fall into one of the above cases:

Using NI-VISA 3.0 to Control Your USB Device

http://zone.ni.com/devzone/conceptd.nsf/webmain/6792bab18242082786256dd7006b6416 

What is USBTMC and how can I Communicate to my USB Instrument Using NI-VISA?

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000x1qzCAA&l=en-US

Why is NI-VISA Unable to Control my USB Device?

http://digital.ni.com/public.nsf/allkb/273BB58D3B52CE6886256F3B00714D03 

Using NI-VISA to Emulate a USB Device

http://digital.ni.com/public.nsf/allkb/569EED7D5B15541686256F7A0068D56D 

VISA USB RAW Mode Get Interrupt Data Example

http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=DC76651CD1522404E034080020E74861 

Let me know if you have any further questions.