For a connection to exist between two media devices, the connectors on each device must be of compatible types. For instance, a connection could be established between the line OUT connector on one device and the line IN connector on another device, however a connection between line OUT and video IN is prohibited. This mechanism will eliminate the majority of incorrect connections. The following table lists the allowable connections based on connector types. These connections are allowed in either direction. Please note that this table should be read as meaning that a device which has a connector of the type in the first column can connect to a device which has a connector of the type in the second column.
┌───────────────┬───┬───────────────┐ │amp stream │<->│wave stream │ │ │ │midi stream │ │ │ │cd stream │ │ │ │xa stream │ ├───────────────┼───┼───────────────┤ │line in │<->│line out │ │ │ │audio out │ ├───────────────┼───┼───────────────┤ │audio in │<->│headphones │ │ │ │speakers │ │ │ │line out │ ├───────────────┼───┼───────────────┤ │video in │<->│video out │ ├───────────────┼───┼───────────────┤ │headphones │<->│audio in │ │ │ │line in │ ├───────────────┼───┼───────────────┤ │speakers │<->│audio in │ │ │ │line in │ ├───────────────┼───┼───────────────┤ │microphone │<->│audio out │ ├───────────────┼───┼───────────────┤ │phone line │<->│phone set │ └───────────────┴───┴───────────────┘
The connections in the table shown above are based on connector types, not device types. The list of connections might appear incorrect if the connector types are misinterpreted as device types. For example, "headphones <-> audio in" might be misinterpreted as meaning that headphones can be connected to an audio input. Referring to however, we see that the HEADPHONE device has a connector of type audio in. This connector is analogous to the plug on the headphones and, from the perspective of the headphones, it is input. We also see that the AMPMIX and CDAUDIO devices have connectors of type headphones. The connection is correct, because headphones can be connected to either the CD player (CDAUDIO) or to the audio adapter (AMPMIX).