Selecting signals for extraction from a bus

Bus selector

As mentioned in the previous section, all information about a signal bus is propagated from its origin point, the creator component, towards the consumption point, which is the Bus Selector component.

By default, the Bus Selector component has a single output port when dropped on the sketch. Similarly to Bus Creators, clicking on the component activates the Edit bus mode of the Sketch contextual toolbar button, which gives access to the signal extraction dialog window:

Figure 410: Extracting signals from a bus

As an illustration of the propagation mechanism, below is the same bus, viewed (in its hierarchical form) at the Bus Creator which generates it:

Figure 411: Bus inputs available in the selector

To extract signals from a bus, all the user needs to do is select the signals of interest in the Bus data pane, and move them over to the Outputs pane. The component in the sketch will automatically adapt to the last defined set of outputs.

Note

• It is possible to extract any type of signal from a bus - if you are working with a nested bus structure, it is possible to extract the entire bus, or one if its nested sub-buses, or a single variable within a nested bus. As an illustration, the last two elements extracted from the incoming bus in figure Figure 410 are buses nested within the parent bus: the CAN and ENV buses.

• When extracting a single variable from a nested bus, the hierarchical information is conserved by means of structured naming in the text identifiers. This is clearly shown for instance when looking at the signal GUI.drivermode in the figure Figure 410, which implies that the drivermode signal is contained within the GUI sub-bus of the bus currently being extracted from. Generally speaking, the naming convention will take the form SubBusLevelN.SubBusLevelN-1. ... . SubBusLevel1.SignalName for an N+1-level bus.

• When a bus is selected for extraction from a bus, the output port on the Bus selector component corresponding to that object will automatically become a bus port. In the Bus selector dialog window, children of an extracted bus are non-modifiable - it is possible to re-order the outputs of a bus selector, but if a bus is extracted, all of its contents (signals, order and hierarchy) are conserved, and in read-only mode.

• When vectors are inserted into a signal bus, they are added as monoliths, i.e. the vector and all of its components are treated as a single entity. It is for instance not possible to insert an individual vector component into a bus, nor is it possible to extract an individual vector component from one. The same applies to groups of variables.