“Learn how to create a real time MIDI synthesizer with spectrum visualization and no RTOS using a Raspberry Pi Pico
The Raspberry Pi Pico is an extremely popular and capable MCU (microcontroller) development platform that is based on Raspberry Pi’s RP2040 MCU and costs only $4. The RP2040 incorporates two 133 MHz Arm’s Cortex-M0+ CPU cores, 264 kB of SRAM and a unique programmable I/O system.
This guide will walk through the integration of several software components to create a MIDI player with spectrum visualization and animations. I will explore how we can create a complex software, with real-time audio synthesis, visualization and dual-core without using an RTOS.
The audio will be generated using the PWM audio driver from the pico-extras and the LCD will be controlled with the LCD driver from the PIO pico-examples (modified for the demo).
The software components will be integrated using the CMSIS-Stream open source library.
MIDI components come from the Playtune Synth project by Len Shustek and have been modified a lot to be integrated in this demo.
The demo uses the two M0+ cores.”