Added detailed instructions about the setup.

Demo_Eth_GR740_to_PC/README.md

+
+The setup required to make this sample application work, involves
+connecting your GR740 board to a Linux machine via Ethernet.
+This could mean a direct connection via a cross-over cable,
+or a more normal setup involving an Ethernet switch.
+
+Things to do first:
+
+1. If you check the [GR740 board's user manual](https://www.gaisler.com/doc/gr740/GR-CPCI-GR740-UM.pdf),
+   you will see that on page 17, Figure 4-8, there's a diagram indicating that the
+   ETH1 interface is only connected if J22 is connected. Note that connector J22
+   exists at the bottom side of the PCB - so flip your GR740 and look at the PCB:
+   if you see the same picture as that shown in Figure 4-9, you must move the
+   configuration plug to the middle location (J22).
+
+2. On your Linux machine - the one that will run the `binaries/x86_partition` - you
+   need to make sure that the network configuration mirrors the values input in
+   the DeploymentView:
+
+    $ grep 192 DeploymentView.aadl
+    Deployment::Configuration => "{devname ""eth1"", address ""192.168.0.151"", port 5116 }";
+    Deployment::Configuration => "{devname ""greth1"", address ""192.168.0.42"",
+      gateway ""192.168.0.1"", netmask ""255.255.255.0"", version ipv4, port 5118 }";
+ 
+   Put simply, the default configuration assumes that in your Linux machine, there's
+   a second Ethernet interface (`eth1`) that has the IP address 192.168.0.151.
+
+   So in addition to connecting the GR740 board with the Linux machine via an Ethernet
+   cable plugged-in at the bottom right Ethernet jack of the GR740 board, make sure 
+   that the Ethernet interface is also set up:
+
+    $ sudo ifconfig eth1 192.168.0.151 up
+
+   ...otherwise, if you use a different configuration, edit this line in the DeploymentView
+   AADL file and change it to mirror yours. You can change the 192.168.0.151, provided that
+   you stay in the 192.168.0.x subnet.
+
+3. Don't change the 192.168.0.42 address of the GR740 side of the Ethernet, however,
+   because this address is currently hardcoded in the PolyORB Ethernet driver.
+   The PolyORB team is investigating ways to improve this; in older versions of
+   RTEMS it was possible to modify the IP address after bootstrapping, but in
+   RTEMS5.1 apparently this is not possible anymore. 
+
+That should do it - you should be able to launch the `x86_partition` in your Linux machine,
+and the `gr740_partition` in your GRMON, and see the setup work.