I can't check the "Include Vissim Communication Interface" option in the "Code Generation Interface"

For debugging reason, I need to compile a diagram using the "Include Vissim Communication Interface" option in the "Code Generation Interface". But this option is disabled. I search, but I don't find how to enable this option. Can you help me ?

I've got Vissim 7.0 and I want to compile for the processor TMS320F2407 on the F2407 evaluation bord.

what is a compound block

You must select a single compound block first.

You must first select a single compound block in your diagram before invoking Tools > Codegen to enable the Include VisSim Communication Interface option. When you select this option, VisSim will generate code for the compound block so that the resulting .out file will expect the same number of inputs and outputs from the PC as the selected compound.
By convention, do a Save As... of the source diagram to a "-d" suffixed version after you replace the selected compound block with a DSPInterface block and set the Simulate > Simulation Properties > {Run in Real Time, Time Step = .01}. The placed DSPInterface block will have the same pin count as the generated compound, and will come preconfigured with the path to the .out file you just created. There is no reason to run the debug diagram at a faster sample rate than .01 sec due to limitations in the speed of the JTAG interface. This is only done once at the start of a project, so you will now have a source diagram and a "-d" suffixed debug diagram. When you click "Go" for the debug diagram, the DSPInterface block will download the .out file created by Codegen. You may now provide values to the target via the input pins of the DSPInterface block using the slider and button. You can also plot monitor buffer vector output in a plot block to get digital scope response of internal signals on the target at the full target sample rate (>500kHz).