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QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
Utilities & Libraries
Utilities Reference
P
pcm_logger
Log Pulse Code Modulation data

QNX Momentics IDE User's Guide
This User's Guide describes version 7.1 of the Integrated Development Environment (IDE) that's part of the QNX Momentics tool suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
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- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX Neutrino RTOS system and developers who want to create a QNX Neutrino resource manager free from vulnerabilities.
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        Resource manager process that manages the PCI hierarchy
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        Log Pulse Code Modulation data
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        Process-level debugger
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        Packet Filter pseudo-device
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        Packet filter configuration file
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Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

pcm_logger

Log Pulse Code Modulation data

Syntax:

pcm_logger [options]

Runs on:

QNX Neutrino

Options:

-a card_num:dev_num: The card number and the device number of the target PCM device.
-c card_num[:card_num...]: A list of cards to apply the logging operation to. The PCM logging operation applies to all PCM devices under the specified cards.
-i: Use interactive mode: wait for a key press to disable logging.
-l[0|1]: (el) Enable (1) or disable (0) io-audio PCM logging.
-m[playback|capture]: Use this option with the -a option to target a playback or capture PCM device.
-v level: Set the io-audio verbosity level.
Note:
The verbosity level applies globally across io-audio. If multiple instances of io-audio are running, use the -c option to target a card that's under the instance of io-audio that you want to affect.

Description:

The pcm_logger utility lets you dynamically enable and disable the logging of PCM data to /dev/shmem and configure io-audio's verbosity level at runtime.

When PCM logging is enabled, the captured audio will be saved in .wav files in /dev/shmem. The names of the wave files specify the card and device from which the audio was captured:

[playback|capture]_card_device_date-time.wav

Page updated: March 12, 2026