The DatanoiseTV PicoADK Is a Raspberry Pi Pico Spin-Off for High-Resolution Audio Experimentation
Supporting 32-bit audio at up to 384kHz, this spin on the Raspberry Pi Pico extends each header by four pins and clocks in at 400MHz.
Semi-pseudonymous maker Sylwester "DatanoiseTV" has put together a Raspberry Pi RP2040-powered gumstick-style development board designed for audio work: the PicoADK Audio Development Kit, also known as the PicoADK+.
"The PicoADK is a RP2040 based Audio Development Kit, which allows you to build your own digital oscillators, synthesizers, noise boxes, and experiment around," Sylwester explains of the breadboard-friendly development board. "It has all the base features of the Raspberry Pico, plus a high quality audio output, 8 analog inputs for connecting potentiometers, control voltage from Eurorack systems, or even additional input signals."
The heart of the board, like the Raspberry Pi Pico, which served as its inspiration, is a Raspberry Pi RP2040 microcontroller with a dual-core Arm Cortex-M0+ processor running at a stock 133MHz but overclocked to 400MHz in the PicoADK. There's 264kB of static RAM (SRAM) and 2MB of SPI flash — "plenty," Sylwester promises, "for synthesizers and sound generators."
Elsewhere on the board are separate very low-noise low drop-out (LDO) regulators for the digital and analog circuitry, a PCM5100A 32-bit I2S audio codec chip offering support for up to 384kHz audio, an eight-channel 12-bit analog to digital converter (ADC) supporting up to one megasamples per second (1MS/s) and with low pass filters on each input plus user-configurable 5V range.
For those who have already been experimenting with the Raspberry Pi Pico, the PicoADK offers "partial" pin compatibility — "besides a few pins internally used or rearranged," Sylwester explains — with the eight additional ADC pins brought out as four extra pins to the far end of the board. At the other end, meanwhile, is a USB Type-C connector — an upgrade on the micro-USB of the Raspberry Pi Pico — which Sylwester says can handle up to 15W of power.
For software, Sylwester provides a FreeRTOS template — which overclocks the processor to the 400MHz level mentioned above — with optional firmware for Arduino IDE, MicroPython, and CircuitPython, though in a "purely experimental and […] early untested stage," Sylwester warns.
Design files for the board are available on Sylwester's GitHub repository under the permissive MIT license, while assembled boards are available to order for $32.99 on the DatanoiseTV Tindie store and at Schneidersladen in Germany.
Main article image courtesy of Paul D. Pape, Schneidersladen.