Pulse Code Modulation (PCM) Developer Guide#

About This Guide#

Pulse Code Modulation (PCM) on SiWx917 provides a high-quality, full-duplex digital audio interface between the system-on-chip (SoC) and external audio devices such as codecs, analog-to-digital converters (ADCs), digital-to-analog converters (DACs), and digital signal processors (DSPs).

The PCM peripheral operates in the High-Performance (HP) domain and is intended for low-latency voice and audio applications, including voice processing, Voice over Internet Protocol (VoIP), audio recording and playback, and codec interfacing.

This guide explains how to bring up PCM using Simplicity Studio and the WiSeConnect software development kit (SDK), configure direct memory access (DMA) streaming, validate signal timing with a logic analyzer, and manage power-state transitions.

Audience#

This document is written for:

  • Embedded and application engineers integrating audio into SiWx917 devices.

  • System designers validating audio interfaces with external codecs.

  • Test and validation engineers performing audio bring-up.

Prerequisites: Familiarity with basic digital audio concepts (sample rate, bit depth, and channels) and experience using Simplicity Studio and the WiSeConnect SDK.

Purpose#

The purpose of this guide is to help you:

  • Accelerate development using step-by-step instructions and tested PCM examples.

  • Leverage SiWx917-specific features, including DMA-based and low-power audio operation.

  • Enable high-fidelity audio communication with best practices for configuration, synchronization, and debugging.

Scope#

This guide covers:

  • PCM peripheral architecture and software integration on the SiWx917 SoC

  • Initialization, configuration, API usage, low-power streaming, and DMA-based operation

  • Debugging, troubleshooting, and optimization of PCM-based audio systems

  • Best practices for reliable, synchronized, and power-efficient PCM communication

Hardware and Software Components#

To complete the tasks described in this guide, you need:

  • SiWx917 IC and module evaluation kits (Supported hardware list)

  • Simplicity Studio IDE (Download here)

  • WiSeConnect SDK (GitHub repository)

  • Audio accessories, such as external codecs, MEMS microphones, or DACs

  • Debugging tools, including a logic analyzer and serial console for validation

Tip: PCM is ideal for voice, single-channel, and low-latency audio applications where precise timing and power efficiency are critical.