Analog measurement WITHOUT DAQ device

[Miaa]

Hello everyone,

I have an analog voltage which is varying between -10volts to +10volts. Is it possible to measure this analog voltage using LabVIEW software without DAQ ? If not kindly suggest the options available for DAQ device.

In the traditional interfacing techniques which uses parallel port and/or serial port. We can acquire signal using C language and inport and outport commands.And no DAQ is required.... I was hoping if LabVIEW can be used without a DAQ device.

I know that RS232 and parallel port can be used but how will the space and mark levels be used for acquiring an analog signals.

[Dennis_Knutson]

The parallel and RS-232 ports cannot be used for analog acquisition with C or any other language. I don't understand how you think these are traditional techniques. Though the voltage levels are different, both ports are essentially digital ports where on/off signals are inputs/outputs.

For your options for an analog data acquisition device, just click on the 'Products & Services' link on the top of the page. In the middle of that page, there is another link to 'Data Acquisition'. I think the lowest cost device that NI makes is the USB_6008.

[mishklyar]

Hello Miaa,from your description I can think about two things,that remind me the days when there where no sound cards

at all computers,but people found the ways to produce sound from PC:

    1)   

             Output:  you can get from your LPT 8 bit analog output if you connect all 8 data pins to one.

             Input:  it probably possible to get 8 bit input,but you need to use some resistors,and have some knoledge in electronics,

                         in order not to burn your LPT with 10 volt input.

           Again,it's possible but not trivial way.

   2)    In general (very): one can get "analog output" even from 1 bit connection,

           in order to do it, the connection speed should be fast enought,and the illusion of "anlog output" reached by changing

          the ON/OFF state of the connection,in right way (playing with delays between ON/OFF,according to signal).

          About "anlog input" using serial port I can say nothing.

In any case,this is very intersting but time cossuming issue,but if you know how to do it,the LabView part is not a problem,

you have there access to parallel and serial ports.