|Scope:||Decode RDS and TMC messages|
|Status:||free time project|
The Video4Linux interface for FM radios also provides a pretty simple RDS data output - given that the FM radio hardware supports raw RDS data output. The RDS-TMC software can interpret the RDS data groups, decode the RDS information (station ID, radio text, frequency lists, etc.) and can forward TMC data packets to the TMC decoder.
The TMC decoder can interpret standard TMC messages (not TMPpro which requires a commercial license). For presenting human readable results a so called "location list" (LCL) is needed. This "list", which is rather a big database, contains expansions from location IDs to location names, event codes to event names and much more.
The location lists are country specific and sometime hard to get. They are either managed by government organisations or private companies. For some countries the lists can be acquired for free, some can only be acquired after licensing. For Germany the raw list can be ordered for free, just redistribution of the raw list is prohibided.
The TMC decoder uses a SQLite database for storing the location list. The GIT provides a ready-converted version of the German LCL which can be used out of the box.
GIT project download: http://git.kernelconcepts.de/?p=rdstmc.git;a=summary
I have modified the Nokia N900 FM radio RDS driver so that it outputs the RDS data in a V4L compliant way to its /dev/radio1. The pre-compiled kernel module can be downloaded here. Simply copy it to the modules directory and restart the radio application (device).
The stuff above was made by me, Nicole Faerber. If you have question, comments or want to talk to me about it, contact me at email@example.com.