The Raspberry Pi Foundation’s tiny computers can be used for anything from homemade cameras to cucumber sorters, and now, the group is branching out into microcontrollers and custom silicon. The Raspberry Pi Pico is the first step. It’s a new $4 microcontroller that’s smaller than the average Pi, features a custom chip powerful enough to be used in machine learning projects (according to The Raspberry Pi Foundation), and is on sale now.

In its introductory blog post, the company explains that today’s Raspberry Pis are already often used alongside a smaller microcontroller:

The Raspberry Pi takes care of heavyweight computation, network access, and storage, while the microcontroller handles analogue input and low-latency I/O and, sometimes, provides a very low-power standby mode.

Now, the company has one of its own.

In a first for the microcomputer maker, the Pico is powered by a custom chip designed in house called the RP2040. The Pico board features the new chip, 2MB of flash memory, a clickable button, and a Micro USB Type B port. Here are the RP2040’s full specs:

Dual-core Arm Cortex-M0+ @ 133MHz
264KB (remember kilobytes?) of on-chip RAM
Support for up to 16MB of off-chip Flash memory via dedicated QSPI bus
DMA controller
Interpolator and integer divider peripherals
30 GPIO pins, 4 of which can be used as analogue inputs
2 × UARTs, 2 × SPI controllers, and 2 × I2C controllers
16 × PWM channels
1 × USB 1.1 controller and PHY, with host and device support
8 × Raspberry Pi Programmable I/O (PIO) state machines
USB mass-storage boot mode with UF2 support, for drag-and-drop programming

Those specs might go in one ear and out the other, but the best way to illustrate the potential for a new Raspberry Pi product is to see it used in something cool. The Raspberry Pi Foundation is partnering with companies like Arduino, Adafruit, and Pimoroni to integrate the new RP2040 chip into other boards and gadgets. There’s a whole list in the blog post announcing the Pico, but a few notable ones are Pimoroni’s PicoSystem game console, Adafruit’s Feather RP 2040 board, and the Arduino Nano RP2040 Connect.

The Raspberry Pi Pico is available now from approved resellers for $4. The microcontroller will also be given away for free in February issues of HackSpace magazine.