Display a graph from data stored on SD card

Hi there,

I have a project that saves the values from the analog input on a SD card in CSV format, and I'm trying to display a line chart on a Webserver using data stored in the SD card (i'm using the ethernet/SD shield), but I can't figure out how can I do this.

I've saw some examples on the internet but they get real time measurements, and in my case I will have the values already stored.

moisesdias:
Hi there,

I have a project that saves the values from the analog input on a SD card in CSV format, and I'm trying to display a line chart on a Webserver using data stored in the SD card (i'm using the ethernet/SD shield), but I can't figure out how can I do this.

I've saw some examples on the internet but they get real time measurements, and in my case I will have the values already stored.

I want to be sure I understand what you're asking:

You want to:

1.) Have the Arduino log data in CSV format
2.) Display the data on a webserver from the SD card

Which part are you having issues completing, recording the data in CSV or porting it to a webserver?

In fact, unless you're not constantly connected to a webserver with the Arduino, the SD card isn't really needed. However, if you're issue is with the record formatting you'll want to program the Serial to print in the format of a CSV if you're feeding directly to the webserver.

Ex

Serial.print("valueA");
Serial.print(",");
Serial.print("valueB");

But if the information needs to be saved to the SD, then set up the card and roll with doing the same to a file (replace "Serial" with "sdFile" or whatever you call the file created by the Arduino on init).

Have a look at the function I posted. At one point I had code to retrieve a .csv file and plot the data. let me look around. in the meantime, is this what you are looking to do?