Hi all,

(I speak as a complete newbie, so keep that in mind...)

What would be a good approach to logging the voltages from a simple circuit. For example, if I want to make a graph of the voltage across a capacitor as a function of time, I would want to make a csv file of the voltage at a bunch of time points, and have that file on my computer. How would I do that, as simply (and cheaply) as possible?

Maybe oscilloscopes have plugs for this kind of thing? Any other ideas? It would be best if the solution were Unix/ Linux based but I can deal with Windows as well.

 

A simple USB oscilloscope starts at a few $ on Ebay.

An Arduino, with a simple program to send samples over the USB cable to the PC. It is one of the simple example programs on the Arduino web site...

 

A simple USB oscilloscope starts at a few $ on Ebay.

An Arduino, with a simple program to send samples over the USB cable to the PC. It is one of the simple example programs on the Arduino web site...

Or an Arduino with an SD card shield. The data can be written to the SD card in csv format, which is subsequently read by a PC with an SD card reader.

 

Hi all,

(I speak as a complete newbie, so keep that in mind...)

What would be a good approach to logging the voltages from a simple circuit. For example, if I want to make a graph of the voltage across a capacitor as a function of time, I would want to make a csv file of the voltage at a bunch of time points, and have that file on my computer. How would I do that, as simply (and cheaply) as possible?

Maybe oscilloscopes have plugs for this kind of thing? Any other ideas? It would be best if the solution were Unix/ Linux based but I can deal with Windows as well.

It depends on the speed of your signal. Are you talking seconds to milliseconds or mSec to microseconds?

Seconds to milliseconds - use the analog to digital converter on arduino. Use code as mentioned above.
If you need faster, look for a national Instruments data acquisition board to connect to your computer (about $200 on eBay).

 

Also really need to know what resolution, if the guy wants hi-res then an Arduino might not cut it unless it has an external A/D module.

 

Thanks for the replies. The answer seems to be the Arduino board for my applications -- low res is fine for now. The data acquisition board will be for later.