--- a/README	Mon Jan 10 19:07:49 2011 +0100
+++ b/README	Mon Jan 10 19:13:26 2011 +0100
@@ -17,6 +17,25 @@
 SUBSYSTEM=="usb", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="0003", MODE:="0666"
 
 
+* GNUPLOT
+
+In order to show graphs, you can setup gnuplot this way to say for example the downloaded
+data in a.txt. If the header reads:
+# Start: 2010-11-27 23:4:28
+# Num Samples: 1118
+# Time between samples: 30 s
+
+
+You can use the unix command date to transform that into a timestamp:
+$ date '+%s' -d '2010-11-27 23:4:28'
+1290895468
+
+Then in gnuplot you can run, considering the values of 1290895468s since the epoch and
+samples every 30 seconds:
+> set xdata time
+> plot "dutxa.txt" using ($1*30 + 1290895468):2, "dutxa.txt" using ($1*30 + 1290895468):3
+
+
 * LICENSE
 
 The code is licensed on terms of the GPLv3 license or later. Please find the license in the file