To add an interface to components use the different AUTOSAR Port elements, available in the LieberLieber AUTOSAR Engineer toolbox. Set name and type (property type) in the port options. The direction and if a Port is a Service Port must be set in the Tagged Values of the Port:
To connect two ports use the AUTOSAR Flow Connection connector. You can also use the Enterprise Architect Quick Linker to connect two ports or create a new port and a connection in one step, by creating a connector between an existing port and a component. The LieberLieber AUTOSAR Engineer will assist you by automatically setting name, port type and direction of the new port when undefined!
Port Direction Determination
For being able determin set the port direction correct, you must add a UML Compose or a SysML Part Association connection (black diamont) to define the hierarchy of your components. These will define "this component is a sub-element of the other" and the tool can set the direction in a correct manner. The following diagram shows an example of such a component hierarchy specification (Decomposition View):
The diagram below shows an AUTOSAR Diagram with components, interfaces and interface connections (Architectural View). The option "Show element Stereotypes" is disabled for the diagram.