Convert analog input to digital output

[RODAWG]

Is there a way I could receive an analog input using RS232 cable at serial port in Labview and convert it to digital using Labview???
Thanks

[ryank]

A serial port is a digital input, with TTL voltage levels. Connecting an analog signal to it would not be meaningful. In order to digitize an analog signal you need something with an Analog to Digital Converter, such as a DAQ board, oscilloscope or digitizer.

Regards,
Ryan K.

[Conseils]

The principle of the answer is that the RS232 channel understands only two states 0 or 1.

Your signal source (analogue) has an infinate number of states. Perhaps you don't need this much data?

What you need to do is condition the signal in some way if you wish to use the RS232 port.

Could you use a sound card input instead?

If you use a sound card, I strongly advise conditioning the signal. But it's a very low cost solution and practicle if the original signal comes from a low voltage battery powered device.

Put more detail on line about what you are trying to do, I am sure you will get a good response.

[RODAWG]

Thanks for your response.
This is what I am trying to achieve.

I have been working on a wireless vital sign monitor that takes heart signal, oxygen concentration and temperature signals using sensors and elecrodes. The signals are then filtered and amplified in the range of 0-5 V.
The microcontroller is the next section that is responsible to package the signal, transmit them wireless, receive them wireless and send them serailly using RS232 cable to PC in the format (delimiter1)signal1(delimiter2)sigbal2(delimiter3)signal3.
The labview then finally separates the data, analyses them and displays the results digitally and in waveforms.

That was the initial plan. The microcontroller chip has blown up and I have less than a week to present this project. I have all other parts working but don't know how to present my project and how to demonstrate in the most efficient way.

I was thinking about displaying one signal at a time but then without the microcontroller, I will not be able to sample the data from A/D.
I thus thought of using analog signals and receiving them in labview but I also dont have access to any other hardware such as DAQ or so.

Any advice.
Thanks

[ryank]

You are going to need some sort of additional hardware, Conseils's suggestion of a sound card is a good option since they are inexpensive and you can pick one up at any computer store. Depending on the channel count, frequency, accuracy, signal conditioning, etc that you need, this may be an acceptable solution. DAQ boards are now faily inexpensive, but if you need to have something this week you're probably going to have trouble getting one in time.

Regards,
Ryan K.

[Conseils]

It is my experience of student projects both personal and professional, that the most important point is to present a clear and well considered project report based on what has been learnt during the course. It's a chance to demonstrate how you might or have applied what you have been studying in your own words.

I speak now from personal experience, I was assigned a project to work on a motor control system. In our haste to get things up and running, we blew up one of the control modules. Our tutor was none to pleased - what with budgets being extremely restricted. He threatened to give me and my colleague a zero for the assessment. Not good news as we were being paid rather well at the time and our pay was based directly on performance.

We therefore offered to fix the problem and submit a report based on a theoretical analysis (much more difficult than the practical). I remember our tutor was more impressed with our commitment and problem solving approach (as well as the content of our report) than anything else. We passed with flying colours (otherwise I wouldn't be on this forum) ohhh... We also redesigned the module circuit so that other students couldn't make the same mistake.

The point of the story is that failure and mistakes are a part of life, it's what you do about it that matters!!


Good Luck

[rpursley8]

You might be able to use a joystick port to do it if you have one on your PC.

This link has some info on that

http://www.pages.drexel.edu/~kws23/JoyWin.html#The%20Game%20Port