Add gnuplot_rigol_ds1xx2.gpi gnuplot script.

This is a very simple gnuplot script for testing the Rigol DS1xx2 driver.
It currently has various issues and limitations (e.g. only one channel
is displayed, the scaling is not usable, and so on) to be fixed later.

contrib/Makefile.am

@@ -19,6 +19,7 @@
 ##
 
 EXTRA_DIST = gnuplot_chronovu_la8.gpi \
+	     gnuplot_rigol_ds1xx2.gpi \
 	     gnuplot_usbeesx.gpi \
 	     gnuplot_usbeedx8.gpi \
 	     gnuplot_usbeedx16.gpi \

contrib/gnuplot_rigol_ds1xx2.gpi

@@ -0,0 +1,37 @@
+##
+## This file is part of the libsigrok project.
+##
+## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, write to the Free Software
+## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+##
+
+set terminal png large size 2048, 1536
+set autoscale
+set grid
+set title "sigrok gnuplot output, http://www.sigrok.org, Rigol DS1xx2"
+set xlabel "Time"
+set ylabel "Voltage"
+set output "sigrok_gnuplot.png"
+
+#
+# Rigol DS1xx2 output is currently always 600 samples in size.
+# This script currently also assumes only one channel is acquired like this:
+#
+#   $ sigrok-cli --driver rigol-ds1xx2 --frames 1 -p CH1 ...
+#
+plot [0:600] \
+"sigrok_gnuplot.dat" using 1 with lines linewidth 2 title "CH1"
+