I wrote an extension to the BlueMp3 firmware. Now you can use an loudness filter on the mp3-player. After reading the VS1001 specs, the BlueMp3 mp3-decoder, i noticed that it’s possbile to upload code to the dsp.This code can manipulate the current mp3 stream, so perfect for a loundness filter. I worked through the VS1001 application note and wrote some routines to upload that VS1001 code to the chip. Then i integrated that routines into the BlueMp3 firmware. There is patch available for the 1.8 firmware but also the binary 2.5 firmware includes the loundness filter code.1 Comment
After reading the CT article about the BlueMp3 player, i knew i need this piece of hardware. It’s an bluetooth mp3 player based on the Atmel Mega128 cpu. The firmware source is available and the client is linux based. So what do i need more to play around? I ordered the pcb and parts at Segor. The Bluetooth module and the Atmega was pre-solderd, because it’s not easy to solder TQFP’s at home. The thing was build after a hour of soldering and worked perfect. But the bluetooth signal just worked over 5 meters. So i added an Lambda/4 antenna (thanks tobi) to the bluetooth module, which extented the coverage up to 20 meters. But what i really needed was a GUI to play my mp3s. Since iam KDE user i deciced to programm my own Gui called k2send. I setup a project page a berlios for it.