make jack audio from gpio beaglebone - audio

I need to play a mp3 file in beaglebone black rev C. Unlike raspberry, BBB does not have jack audio. I have USB audio adapter, but I want to build a new jack audio using GPIO pin in BBB.
I installed arch linux in my BBB and use mplayer to play mp3 file.
Could you help me?

You can use PWM pin to modulation audio signal! Begin you need decoder mp3 to pcm code.![enter image description here][1]

Related

ALSA Card for Respeaker 4-Mic Setup

During the installation, we are supposed to check the sound card by pressing ‘arecord -L’ to obtain a certain output like shown below,
pi#raspberrypi:~ $ arecord -L
null
Discard all samples (playback) or generate zero samples (capture)
jack
JACK Audio Connection Kit
pulse
PulseAudio Sound Server
default
playback
ac108
sysdefault:CARD=seeed4micvoicec
seeed-4mic-voicecard,
Default Audio Device
dmix:CARD=seeed4micvoicec,DEV=0
seeed-4mic-voicecard,
Direct sample mixing device
dsnoop:CARD=seeed4micvoicec,DEV=0
seeed-4mic-voicecard,
Direct sample snooping device
hw:CARD=seeed4micvoicec,DEV=0
seeed-4mic-voicecard,
Direct hardware device without any conversions
plughw:CARD=seeed4micvoicec,DEV=0
seeed-4mic-voicecard,
Hardware device with all software conversions
usbstream:CARD=seeed4micvoicec
seeed-4mic-voicecard
USB Stream Output
usbstream:CARD=ALSA
bcm2835 ALSA
USB Stream Output
However, the output that I have received is as shown below,
Screenshot of Output
It basically shows that I don’t have the ALSA soundcard, and I cant move on to the sound localization process. Please show how can I move forward, thanks!

How to debug a Linux I2S audio input issue

I am trying, and failing, to connect an I2S microphone (Invensense ICS43432) to my Raspberry Pi (B+) running Arch Linux. I have asked for specific advice in the relevant Arch Linux ARM forum but my question is really more general than that: how does one go about debugging Linux audio input issues?
I have verified with a logic analyser that the I2S microphone is sending sensible data in the correct channel (left) and the correct pin of the Raspberry Pi. The I2S microphone appears under ALSA as a "sound card". arecord is perfectly happy to record from that device and I have boosted the gain of that device using alsamixer by 30 dB. Yet all the data bytes of the recorded file are zero.
How does one go about checking the flow of audio data, the operation of DMA, under Linux?
I had the same problem trying to record in stereo, using 2 Adafruit I2S MEMS breakout mics: arecord worked fine, but zeros when using ALSA to write to a bin file. Choosing a 32 bit word format (Little Endian 32 bits, Signed) made it work. Only I end up with 64 bit stereo Frames.

Getting Input from electret microphone max4466

I want to get input from an electret microphone on the raspberry pi 3 in python 3. The electret microphone is max4466 from Adafriut. VCC is plugged into 5.ou, GND is plugged into GND, and OUT is plugged into GPIO 11. I have GPIO 11 set for input, but all I get are 0's. What should I do to get input?
The MAX4466 is an amplifier with analog outputs, not digital ones and zeroes. The GPIO pins are purely digital and can't accept an analog input. In order to digitize the output from a microphone, you need to hook it up to an analog-to-digital converter (ADC). Adafruit sells little ADC boards to help you do this. The ADC digital output would hook up to your GPIO on the Raspberry Pi.
Here's a link to learn about ADCs from Adafruit:
https://learn.adafruit.com/raspberry-pi-analog-to-digital-converters/overview

Arduino UNO audio output with R2R DAC

I'm trying to implement audio output using R2R 8bit DAC and Arduino UNO.
This is my hardware:
http://imgur.com/a/hiUCq
This is the sound i want to hear:
http://vocaroo.com/i/s0VDwBBkQRdc
This is a wav file, 16Khz, mono, 8 bit pcm.
I used matlab to retrieve the binary data from the wav file, and then wrote this code:
http://csharppad.com/gist/0f39da965e31fc838c6de73ff50e5669
I connected the output to some speaker and what i hear is some strange sound..do you think i miss something in my hardware/software?
Thanks!

With Python/PySide/PyQt/Phonon how to control a USB Soundcards output sample clock rate?

I am trying to O/P audio to a USB soundcard (Lindy PnP SoundCard device) via Python/PySide/PyQT by the use of Phonon and/or QTMultimedia.
I can O/P the aduio (mp3/wav) which is no problem - the issue is that I want to control the USB's output sample clock rate, I need to be able to change this from 44.1 to 48 kHz. The soundcard comes with its own s/w that allows this so it is possible.
I can play Audio through Phonon like so..
self.mediaObj=phonon.Phonon.MediaObject(self)
self.audioSink=Phonon.AudioOutput(Phonon.MusicCategory, self)
self.audioPath=Phonon.createPath(self.mediaObj, self.audioSink)
self.audioSink.setVolume(0.3)
However I do not see any way to change the sample clock rate of the USB device from looking at the Class Reference doc's it seems its not possible.
http://www.pyside.org/docs/pyside/PySide/phonon/index.html
So then I have tried to use Qt Multimedia to change the USB soundcards O/P clock rate..
format = QtMultimedia.QAudioFormat()
format.setChannels(2)
format.setFrequency(44100)
format.setSampleSize(16)
format.setByteOrder(QtMultimedia.QAudioFormat.LittleEndian)
format.setSampleType(QtMultimedia.QAudioFormat.SignedInt)
This has no effect. Does anyone know how I would do this and if it is even possible with Phonon/PyQT? I am guessing I need to go lower and try find the USB Soundcard directly which will be messy..
Much appeciate any help!!
Alan

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