Questions tagged [pcm]
Pulse-code modulation
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PCM to dbspl conversion in esp-idf
using i2s interface of esp32-wroom-32 i am getting PCM data from PDM micro-phone. how can i measure acoustic sound pressure level?
below is datasheet sheet of micro-phone.
from 16-bit array how can i ...
- 61
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STM32F7: How to store one cycle of sinewave (1kHz) in array as PCM data?
I'm using a STM32F746 discovery board to learn about digital audio. I'm doing the basics right now. I want to store a single cycle of a 1kHz sinewave in an array and eventually use a DMA to transfer ...
- 1,130
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Interfacting a device's PCM output with a RPi?
I am planning to use a SIM7080G for a future project. However, I am facing an issue with the way it handles audio.
The SIM7080G has a PCM interface, which, according to the hardware design guide, is ...
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How to interpret this PCM audio data?
I am attempting to write a program to get an ATmega328P to play audio. I first tried to use this library but I could not get it to work so I am now attempting to program my own. The problem is that I ...
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Customising audio on an arcade game with U6295 audio IC
I have an arcade redemption game that has a U6295 audio IC that plays 4 different soundtracks which are stored on a ST M27C801 EPROM.
I would like to flash my own audio onto that EPROM with one of ...
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What is the bandwidth formula for pulse code modulation (PCM)?
The image below shows the formula for the bandwidth of pulse code modulation (PCM.) There are two questions I want to ask:
Bandwidth of the PCM signal waveform is bounded by \$ B_{PCM} = \frac{1}{2}(...
- 1,074
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Audio amplifier : how to combine stereo output to mono input
In the following schematic, I would like to decode PCM audio from my Raspberry Pi and output the signal to a 3W speaker. The PAM8302 datasheet is quite light. I don't understand what the input levels ...
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PDM signal demodulator CIC filter input bit width
In order to convert the PDM stream into PCM samples, the PDM stream needs to be decimated.
Bits in PDM stream can be encoded as 1=> +1 and 0=>-1 and this corresponds 2bits signed number(S2.0). I ...
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How to test Pulse Code Modulated sound signal?
I'm trying to perform a PDM to PCM conversion. The PDM signal is coming from MEMS microphone.
There are different decimation approaches like FIR, CIC, cascade Half Band(HB) filters and so on. How ...
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AKM DAC problem
I’ve been developing the basis for a granular synth and general digital development platform for the past few months. I was using STM32 chips at first, but I’ve switched to bare metal Raspberry Pi for ...
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How to scale audio signal from PCM data to a dB SPL value?
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I've got a set with MEMS microphones that measure audio signals at ultrasonic frequencies. The MEMS microphones have a PDM output which is then converted into PCM (this is necessary to allow for a ...
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What's the benefits to using analog-to-digital conversion like PCM?
I was reading a textbook, Data Communications And Networking, by Behrouz A. Forouzan, which says:
A digital signal is superior to an analog signal. The tendency today is to change an analog signal to ...
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WM8960 on Pi detected but not working
I am trying to create custom board with WM8960 IC with Raspberry Pi. I am able to use Wolfson drivers for pi to detect the IC via I2C but I am not able to play or record any audio. This is the ...
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SMPS: Current Mode Instability (aka “sub-harmonic oscillation”) - Can we ignore it?
Currently I am designing a Constant Current charger for a capacitor which charges it from 0 to 350 VDC using a peak current mode controller.
As we expected from simulation, I see there are sub-...
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Synchronizing an oscillator signal and a single wire signal
On some 32bit MCUs(PIC32MX, STM32F4), those SPI pins can read a continuous signal such as I2S/PCM.
So I thought to read a single-wire signal that has MHz fixed frequency as SPI.
First, I made a ...
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