What are the NMEA 0183 Listener and Talker Designations?
The NMEA have updated the NMEA 0183 specification to ensure a consistent naming convention is used for labelling ports. The designation follows the same rules as used for Rx and Tx labelling but uses the descriptions’ Talker’ and ‘Listener’ instead. The input/receiving (Rx) port on a device will be labelled as a ‘Listener’ port. The output/transmitting (Tx) port on a device will be labelled as a ‘Talker’ port. When a port is labelled ‘Listener’ it is an input and when it is labelled ‘Talker’ it is an output.