User`s guide

xPC Target Interface Blocks to Simulink Models
8-11
Note that you cannot select signals on the output ports of any virtual blocks
such as Subsystem and Mux blocks. Also, you cannot select signals on any
function-call, triggered signal output ports.
1 Open a Simulink model. For example, in the MATLAB Command Window,
type
xpc_tank or xpc_tank1
2 Point to a Simulink signal line, and then right-click.
3 From the menu, click Signal Properties.
A Signal Properties dialog box opens.
4 Select the Documentation tab.
5 In the Description box, enter a tag to the signals for this line.
For example, the block labeled TankLevel is an integrator with a single
signal that indicates the level of water in the tank. Replace the existing tag
with the tag shown below.