Digital/Analog Output with Labview

[Pouya]

How to send digital/analog signals from Labview?
How to communicate with parralel or serial port in Labview?

[Sanjay]

Here's part of your answer:-
For Serial communications use either the VISA-Serial VIs (recommended) or the IO compatibility Serial VIs.

[DaveF 141]

Serial communications - Have a look at the Loopback.vi (believe its in the NI web libraries) for examples of serial communications. Be aware that some serial devices need a "\r" at the end of their command string to actually send out data - apparently Labview does a "\n" instead of a "\r" command. The Loopback.vi may need a short additional wait state (30 ms or so) added to the case statements (and additional step at the end) if it needs to run in a continuous mode. Good luck!
Dave Felt

[Lab Viewer]

Usually, for digital/analog output you need to buy a specialized card to do the job (the type depends on your application specifics and parameters). Some digital related applications (especially those without timing constraints) may be solved via parallel port. For this kind of application and also for communication with parallel port, check:
Setting Individual Bits for the Parallel Data Port Using LabVIEW 
Using the Parallel Port as an Input/Output Channel 
Using the Parallel Port in LabVIEW 

As a start point for serial communication, check LV folder\examples\instr\smplserl.llb and
Serial Communication Starting Point 
Serial Communication General Concepts 

Good Luck

[DaveF 141]

You need something that LabView can talk to which produces the outputs and inputs to a module - either one of the excellent LabView I/O modules, or from other companies (like www.OnTrak.net in Canada - an excellent A/D I/O card that talks serially to a PC). The LabView modules have VIs already prepared for them, and modules from other manufacturers may or may not have VIs written - if not, you get to write your own VIs to communicate either via the parallel port, or the serial port, out to the I/O module(s). Learning how to write VIs from scratch is a steep learning curve; Good Luck and have fun!

[Matt_K]

If you are looking to get a data acquisition board (what you will want to send digital/analog signals from LabVIEW), the following link is probably a good place to start. It will take you to NI's multifunction DAQ boards which will have both digital and analog I/O. As mentioned in a post above, using NI's hardware will make the integration into LabVIEW much easier.

http://sine.ni.com/apps/we/nioc.vp?cid=1037〈=US