10/06/2018 at 20:00 •
I found some time to add another sample of La boîte à musique output for the Hackaday Music contest.
Recording analog is now pretty complicated on modern computer since constructors does not provide line port anymore ... I reused my TI PCM2900 "breadboard" USB sound card, but breadboarding USB and audio is not really efficient : it took me some times to make it works correctly. I'm now willing to design a PCB with Kicad to have a line in/line out soundcard handy.
Anyway, there is a sample with the "Punk-Rock" profile :
02/21/2016 at 19:57 •
After a small revision to the board, I finally ordered it on OSHPark. The revision includes a new stereo pot to control headphone and speaker output volume. I changed the micro USB SMD connector with a through hole mini USD because I had to resolder the SMD part multiple times. Finally I added the possibility to have a functionnal board without optional speaker/amp and battery parts.
Once populated and soldered I discovered that I can't get the initial firmware to work... I originally used mbed but after trying for some hours I couldn't get it working. I imagine that I changed something in mbed directly but impossible to find it out. So I decided to change platform from mbed to libopencm3 plus atomthreads and make a new firmware (almost) from scratch. It was actually a great experience which take only a few hours and new firmware is better than the original one.
New firmware and Eagle schematics and board design are available on a new github repository.
12/30/2015 at 19:03 •
I discovered that my laptop doesn't have any line in to record some music from la boîte à musique. I decided to create a small usb card to do that using PCM2900. I just soldered the chip on a tsop to dip breakout and put it on a breadboard with needed passives.
So here is a first sample randomly generated with seed 272310243 (Dance style) and recorded directly from la boîte à musique analog output : https://soundcloud.com/julbouln/272310243a
More to come !