[ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

This is the new app am working on:

Currently the app just uses fmtx_client and can only set rds name (ps), rds text, the frequency and on/off transmitter. The app now thats v 0.1.0 can only be useful to people who dont know how to use x-terminal to set rds text and etc.. and to people who are bored to type "fmtx_client -t text" to set the text :D.

The goal is to create an app that you will press a button and will automatically scan (with the use of transmitter => no headphones are required) and set the transmitter to the first empty freq found. The app will also start a daemon that will check the signal level of the freq that the n900 is transmitting and if it goes bad (like when driving) will automatically rescan and set the transmitter and the ex. car's reciever (using rds af....hopefully) to the first empty freq found.

Any ideas and help are welcome :).

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

Whooa!!!

Amazing Job!

If you keep like that i'm gonna save same money not buying a bluetooth car stereo.

I don't know much of programming, but I can give a opinion.
If you succeed to integrate E.F.F + T-Control + FM Car Kit (in the repos) you are gonna achieve a full Fm Carkit Solution! Great Job!

And if someday you decide to receive some donations on that project (because you deserve it!) just let me know...

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

Auto re-scanning would be awesome and so helpful. Thanks BLIZZARD.

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

It would be great man!!

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

So your app will control the, car radio, through the RDS with auto scanning the next available frequencies? That is an awesome undertaking . But what if the radio doesn't have RDS will it still scan?

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

i found that si4713, the transmitter chip of N900, fortunately supports rds af. If you google tx_rds_ps_af you can find a lot of info and i even found some code examples.

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

I was briefly looking at doing something similar a while back. I believe it would involve either modifying or replacing fmtxd. The problem I came to, and my understanding of RDS may be less than perfect, is this: You tune a frequency, it uses AF to transmit a list of stations linked to the current station. The radio occasionally checks the other frequencies and if it is stronger than the current, it retunes.

The problem is that if the transmitter changes frequency before the radio, it loses the signal including the AF data. But if the transmitter changes frequency after the radio, the radio won't change because the new station's signal strength isn't as strong. In my case, with the way my car radio (Clarion RD3) works, I could get by with just up and changing frequency without AF, because if my radio loses the signal altogether it will quickly scan the other frequencies and look for a station with the same PI code. So on my radio, I could just change the transmitter frequency and not update the radio, and it would find it. I'd love to hear other views on this though :)

I also wanted to look at using AF to transmit the frequency of my local BBC station, and set the flags for it to use EON. Theoretically, this would get my radio to watch the BBC station and, when they start broadcasting traffic (TA), the radio should switch - like it does when listening to another BBC station. This way I can listen to internet radio and still get traffic reports, but I haven't had time to do much work in this way yet.

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

So.. there isnt any way to change only the frequency of the ex. car's radio using the N900's transmitter?

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

I dunno about that, per se, but it would require some tricky thinking, and it would also depend on the radio's implementation of RDS. For example, I know some use one tuner and cache AF data until the signal is too low, and then try the other frequencies. You could probably make those work. Others seem to have two (or more?) tuners, and periodically check other frequencies in the background, and these will be a little trickier what with the N900 only having one transmitter.

Like I said, my particular radio, as long as the PI is the same (and on the N900, it would be), I can change frequency without doing anything with the RDS and the radio will find it after a couple minutes. It really depends on the radio... The longer a radio will store/cache the AF data (as opposed to only using it when it's present in the radio signal - because as soon as the fmtx changes frequency, the signal, and it's AF data, are gone), the more likely that radio is to change frequency with the N900 without doing a rescan.

Re: [ANNOUNCE] (QT) "T-CONTROL" (= transmitter control)
 

I browse this forums for something like 10 months now and I just registed just to say this:

OMFFFFGGGGGGGG! This app is amazing :D

Keep working on it please, please, please, please :D