Blog Post Actions
Group Actions
Engagement
  • Author Author: packetgeek
  • Date Created: Date Created
  • Views 604 views
  • Likes 0 likes
  • Comments 2 comments
Related
Recommended

Success (kinda) with RDS on the Si4703

packetgeek

Have had some initial success in decoding RDS from the Si4703 FM radio receiver.  I can see 8-character chunks of the decoded output.  Now I need to play with the timing and aggregate the output into a series of words on a single line.  The specs indicate that there's other data in there so additional fun is likely.

 

One of the drawbacks with the current solution is (again) having to use wiringPi.  This time around it's need for the decoder's timeout function.  Should be easy to substitute (knock on wood!).

 

Notes after I get it working...

 

- Tim

  • in reply to zeph

    Thanks for the interest.  I'm trying to avoid using the wiringPi because I'm re-teaching myself to program in C and wiringPi is mostly a wrapper around a number of function (i.e., it "hides" the things that I need to relearn).  Not using wiringPi also makes for a simpler compile.  That said, for things that I haven't learned yet, I'm sometimes forced to use wiringPi.  An example of this would be GPIO pin manipulation from C.  I've only recently learned that, which explains the recent change the init function for the Si4703.

     

    Most of the code requires very little restructuring, even for stuff translated from Arduino programs. I've been breaking the various functions out into stand-alone programs, with the idea of (eventually) building a web-front end to them.


    The RDA5807SP is still beyond me.  Google's translation of the programming manual is confusing.  I've resorted to digging through others' Arduino code and Python scripts.  I'll keep chipping away at it.

     

    In any case, I've been posting the code for various stuff at https://github.com/packetgeek and have been updating it every week or two.  Once I have a working set, I'll post them on Element14 with a PDF.  My vision for the PDF is to discuss the I2C interface and the various issues in getting the different receiver chips to work.  After I finish with the RDA5807SP, I still have the RDA5807M and Si4707 to work.

     

    If you see mistakes or problems in my code, please let me know.  It's been almost a decade since I wrote in C and I've forgot much of it.

     

    - Tim

  • I'm interested to see how your FM receiver project continues to evolve, including your RDS exploration.

     

    Meanwhile - could you say something about why using Wiring Pi is undesirable, why you keep using it anyway (at least temporarily), and how you restructure your code to not need it?

    Thanks