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References: Capturing Real Audio: The I2S Microphone

  1. I2S - Wikipedia - Overview of the Inter-IC Sound serial bus, its separate clock and data lines, and how it transmits two-channel PCM audio between chips such as the INMP441 and a microcontroller.

  2. Microphone - Wikipedia - General overview of microphone technology, including a section on MEMS (silicon) microphones that etch a pressure-sensitive diaphragm directly into silicon with an integrated ADC, the design used in this chapter's INMP441.

  3. Analog-to-digital converter - Wikipedia - Explains how a physical voltage becomes a digital number, the underlying process the INMP441 performs on-chip before ever handing samples to the Pico 2 over I2S.

  4. Making Embedded Systems: Design Patterns for Great Software (2nd Edition) - Elecia White - O'Reilly Media - Chapter 7, "Communicating with Peripherals," is credited for demystifying serial bus timing diagrams like I2S through hands-on, hardware-debugging-first narration of clock, word-select, and data lines rather than abstract spec-sheet language.

  5. The Art of Electronics (3rd Edition) - Paul Horowitz and Winfield Hill - Cambridge University Press - The standard practical-electronics reference, long credited for grounding the analog-to-digital boundary in concrete circuit behavior, building the physical intuition this chapter assumes before describing the microphone's own internal ADC.

  6. What is the I2S Communication Protocol? - DigiKey - Maker-focused tutorial walking through the bit clock, word select, and serial data lines of I2S, directly matching this chapter's three-wire breakdown of the protocol.

  7. class I2S – Inter-IC Sound bus protocol - MicroPython Documentation - Official reference for the machine.I2S class used in this chapter's capture code, documenting readinto(), buffered reads, and internal DMA buffering of audio samples.

  8. Raspberry Pi Wiring & Test, Adafruit I2S MEMS Microphone Breakout - Adafruit Learning System - Step-by-step wiring guide connecting an I2S MEMS microphone's bit clock, word select, and data lines to a microcontroller, reinforcing the pin roles introduced in this chapter.

  9. INMP441 MEMS High Precision Omnidirectional Microphone Module with I2S - components101 - Datasheet-style overview of the exact microphone module used in this course, covering its pinout (SCK, SD, WS, L/R) and specifications referenced throughout the chapter.

  10. How to Plot in Thonny - Medium - Practical walkthrough of Thonny's built-in Plotter feature, showing how printed numeric values become a live scrolling chart, the exact technique this chapter uses to visualize captured audio samples.