Figure 3. Message Fomat and Addressing
Figure Note:
1. PI code = Program Identification code = 16 bits (see
Section 3.2.1.1. and annex D of the RBDS Standard)
2.Checkword + offset “n”=10 bits added to provide error protection and block and group synchronization information
(see Sections 2.3 and 2.4 and annexs A,B and C of the RBDS Standard)
3. Group type code = 4bits A [3:0](see Section 3.1 of the RBDS Standard)
4. Bo = version code = 1bit(see Section 3.1 of the RBDS Standard)
5. TP = Traffic Program Identification code = 1bit (see Section 3.2.1.3 of the RBDS standard)
6. PTY = Program Type code = 5 bits PT [4:0] (see Section 3.2.1.2 and annex F of the RBDS Standard)
7. t1 < t2 Block 1 of any particular is transmitted first and block4 last
Although the common data format is complex across 32 different group types, it can be defined at a high level as follows:
Block 1: Block 1 of every RDS group contains the 16 bit PI (pronounced “pie”) code or program Identification code.
For Europe, the PI code contains in formation related to the country of the broadcasting station coverage area and program reference. IN all cases the PI code, for indentical program on different station will be identical. This information, along with the optional alternate frequency list broadcast in group 0A, can be used for automatically switching between frequencies.