Programme identification
Programme Identification is a service provided by radio stations transmitting Radio Data System data as part of the FM radio broadcast. It is 4-digit hexadecimal number.
The PI code allows the radio to identify the station across different broadcasts / multiplexes. For example BBC Radio 1 has PI C201. It is also used in Digital Audio Broadcasting as Station ID.
PI is globally unique only in combination with ECC.
PI code is usually not displayed on the radio receivers.
In allows listeners to stay tuned to a network whilst travelling across the service area of multiple transmitters. It also allows listeners to a particular network to benefit from cross-network travel news services, traffic flashes and for the flagging of travel-related programming.
The PI Code is also used by the RadioDNS standard.
