Pi Pico Learns Morse Code
Summary
A creative project by [101 Things] showcases a Pi Pico system designed to decode Morse code from noisy audio signals. The innovative device employs advanced algorithms for real-time decoding, typo corrections, and displays statistics on an LCD screen.
Key Insights
What is the Raspberry Pi Pico?
The Raspberry Pi Pico is a compact microcontroller board featuring custom RP2040 silicon with dual Arm Cortex-M0+ cores running at up to 133 MHz, 264 KB SRAM, 2 MB flash memory, 26 GPIO pins, and three ADC channels, making it suitable for real-time signal processing tasks like Morse code decoding.
How does the Pi Pico decode Morse code from noisy audio?
The device captures audio using the Pico's built-in ADC, resamples the signal, applies Fast Fourier Transform (FFT) for frequency analysis, uses narrow filters to improve signal-to-noise ratio, and employs a Bayesian decoding pipeline with typo corrections to handle noisy real-time multi-channel Morse code from sources like SSB receivers.