Hello everyone. I am currently messing with my new cobra II board and the music module. I am trying to find ways to optimize the code so that when the screen updates it doesnt cause the audio to stutter.
When the screen updates the audio slightly stutters, I am using the CP7 and might look at changing the code so that a refresh only a small portion of the screen but I was wondering if anyone knows of any other bottlenecks that I can look into :o)
I have the audio stream running in a different thread and reading 50kb of data from the file at a time to reduce file access reads
Have a thread that reads blocks of music into memory and adds them to a cache object which you build. The reading thread monitors the number of blocks in the cache, and when it gets below a threshold it fills the cache.
Register for the musicFinished event.
Start the music playing with a block from the cache.
In the musicFinished event handler, grab a block from the cache and play it.
Signal the reading thread that you have taken a block.
You have to play with the block size and number of blocks to get the best performance.
Go to Codeshare section of forum and seach for “streaming music”.
I have actually written one that used to cache in one thread and play in another, maybe I need to return to that one and try it again. Do you recon creating my own mp3 player module using a different chip will work or do you think its a limitation of the processor. Its a shame you cant cache more to the chip, would eliminate the need for a constant flawless stream.
I want to create a product that allows your to change settings etc while the music is running, I hope to create a radio module that allows FM/am receiving including RDS which means I need to update the display as the audio plays and it gets new track information :o)
It handles reading the mp3 files from storage. All you do is give the start/stop etc. commands over a uart or spi port. And it’s about the same price as the gageteer music module.
ooo looks very good. I was hoping to develop a second solution that would allow online updates, this wouldnt allow me to upload files to the usb but still possibly a good idea for the car stereo :o)
I’ve built an FM reception module, with RDS/RDBS. Done some of the programming but not all of it. Having some problems making enough time to get the module up and running…
Yeah I am having the same problem. Need the time to sit down and work out how to do a module for the non gadgeteer ports on the Cobra II. Done gadgeteer socket modules before but couldnt work out how to setup the SPI correctly via pins. Sure I will work it out and then I should be ok.
You wouldnt happen to be using this chip/breakout would you?
Once I have done this I need to wire it up so that I can switch audio outputs to my amp, got a free sample chip coming that will hopfully do it on a simple pin select…its all a learning curve though lol.
