What is the Raspberry Pi Pico 2?
The Raspberry Pi Pico 2 is a low-cost, high-performance microcontroller board designed by Raspberry Pi.
At its core, it is a small, single-board computer built around a custom-designed chip, the RP2350.
Unlike its larger Raspberry Pi cousins (like the Raspberry Pi 5), which run a full operating system like Linux, the Pico 2 is a microcontroller.
This means it's designed to run a single program in a loop, giving it direct, real-time control over hardware components like sensors, motors, and displays.
This makes it the ideal choice for embedded systems, where responsiveness and reliability are paramount.Β
The Pico 2 is engineered to be a versatile and powerful tool for a wide audience.
For electronics hobbyists and students, its user-friendly, drag-and-drop programming interface and support for languages like MicroPython offer a gentle learning curve . Β
For professional developers, its advanced features, including enhanced security, more powerful cores, and extensive documentation, make it a viable component for commercial products and secure IoT devices.Β
A key aspect of the Pico 2 is its continuity with the original. It retains the familiar 40-pin layout and castellated module design, which allows it to be used in a breadboard or soldered directly onto a carrier board. Β
This "drop-in replacement" capability is a deliberate design choice, ensuring that the vast ecosystem of accessories, tutorials, and community knowledge built around the first Pico remains relevant. Β
The family includes the base Pico 2 and the Pico 2 W, which adds 2.4GHz Wi-Fi and Bluetooth 5.2 connectivity for wireless projects.Β
Features of Raspberry Pi Pico 2
The Raspberry Pi Pico 2 is defined by the substantial upgrades found in its core components.
Every aspect, from the central processing unit to the memory and security features, has been enhanced to provide a more capable and flexible platform.Β
MicrocontrollerΒ
The heart of the Raspberry Pi Pico 2 is the new RP2350 microcontroller, a significant evolution from the RP2040 chip used in the original Pico. Β
This chip is the source of nearly all the performance and feature improvements in the new board.
Designed entirely in-house by Raspberry Pi, the RP2350 was engineered to deliver higher performance, robust security, and greater flexibility for a wider range of applications.Β
- Upgraded Architecture: The RP2350 moves from the older Cortex-M0+ cores to the much more powerful Cortex-M33 architecture, which includes advanced features like a hardware floating-point unit (FPU) and Digital Signal Processing (DSP) instructions.Β
- Enhanced Interfacing: It features a second-generation Programmable I/O (PIO) subsystem, providing more state machines for creating custom hardware interfaces without loading the CPU.Β
- New Capabilities: The chip introduces a comprehensive security architecture built around Arm TrustZone and offers improved low-power modes, making it suitable for battery-powered and secure applications.Β
CPU CoresΒ
One of the most groundbreaking features of the RP2350, and by extension the Pico 2, is its dual-core, dual-architecture capability.
This gives developers an unprecedented choice of processing cores within the same chip, selectable either in software or by permanently programming the on-chip memory.Β
- Dual Arm Cortex-M33: The default configuration provides two high-performance Arm Cortex-M33 cores. These cores are significantly more powerful than the Cortex-M0+ cores in the original Pico, offering faster instruction execution, DSP capabilities, and a hardware FPU for accelerating calculations involving decimal numbers. This makes the Pico 2 much more capable of handling tasks like machine learning inference, audio processing, and complex mathematical algorithms.Β
- Dual Hazard3 RISC-V: Alternatively, users can opt to use a pair of open-hardware Hazard3 cores based on the RISC-V architecture. This is a major inclusion, as it provides a stable, well-supported platform for developers to experiment with and develop for the open-source RISC-V instruction set, which is rapidly gaining traction as an alternative to proprietary architectures like Arm.Β
Clock SpeedΒ
The Raspberry Pi Pico 2 increases the maximum clock speed of its cores to 150MHz, up from the 133MHz of the original Pico.
While a modest increase on paper, this higher clock speed, combined with the more efficient Cortex-M33 architecture, results in a noticeable performance uplift.Β
Faster clock speed means the CPU can execute more instructions per second, leading to quicker program execution and more responsive control over hardware.Β
Benchmarks have shown that even when clocked at the same speed as its predecessor, the Pico 2's Cortex-M33 core is roughly 30% faster due to its superior design. The bump to 150MHz further widens this performance gap.Β
On-Chip SRAMΒ
The amount of Static RAM (SRAM) has nearly doubled, from 264KB in the original Pico to 520KB in the Pico 2.
SRAM is volatile memory used by the microcontroller to store program variables, manage data buffers, and execute code. This substantial increase has several practical benefits.Β
- More Complex Applications: More SRAM allows developers to write larger and more complex programs, especially in memory-intensive languages like MicroPython.Β
- Improved Data Handling: It provides more room for data buffers, which is crucial for applications involving networking, high-resolution sensor data, or display framebuffers.Β
- Enhanced Performance: With more memory available, the system is less likely to run into memory constraints, which can lead to more stable and performant applications.Β
On-Board FlashΒ
The Pico 2 board comes with 4MB of on-board flash memory, double the 2MB found on the original Pico.
Flash memory is non-volatile, meaning it retains its data even when power is turned off. It is primarily used to store the program code that the microcontroller runs.Β
The increased flash storage means you can deploy much larger programs, store more assets like images and audio files, or implement features like data logging directly on the device.Β
This extra space is particularly valuable for complex MicroPython projects, which can have larger codebases and require more storage for libraries and modules.Β
Security FeaturesΒ
Perhaps the most significant upgrade for professional and commercial use is the introduction of a robust and fully documented security architecture.
The RP2350 chip was designed with security as a core principle, moving the Pico platform into the realm of secure IoT devices.Β
- Arm TrustZone-M: At the heart of the security model is Arm TrustZone for Cortex-M, which creates isolated secure and non-secure processing environments on the chip. This allows sensitive operations, like handling cryptographic keys, to be protected from the main application code.Β
- Secure Boot: The Pico 2 features a secure boot ROM that can verify the cryptographic signature of the code before executing it. This prevents unauthorized or malicious firmware from running on the device.Β
- Cryptographic Hardware: The RP2350 includes hardware accelerators for common cryptographic functions like SHA-256 and a True Random Number Generator (TRNG), enabling secure and efficient implementation of security protocols.Β
- Transparent Documentation: Raspberry Pi has committed to a "security through transparency" approach by providing extensive and unrestricted documentation for all security features, allowing developers to audit and confidently integrate the Pico 2 into secure products.Β
Programmable I/O (PIO)Β
The unique Programmable I/O (PIO) subsystem, a standout feature of the first Pico, has also been upgraded.
The Pico 2 now includes three PIO blocks, providing a total of 12 state machines, up from two blocks and eight state machines in the original.Β
PIO allows you to create custom hardware interfaces in software. Essentially, you can define precise, high-speed I/O behaviors that run independently of the main CPU cores.Β
The additional state machines on the Pico 2 mean you can drive more, or more complex, custom peripherals simultaneously.
This is useful for creating interfaces for non-standard protocols, driving multiple strings of addressable LEDs (like NeoPixels), or emulating peripherals like an extra UART or SPI port.Β
Raspberry Pi Pico 2 Pinout
The Raspberry Pi Pico 2 thoughtfully preserves the 40-pin layout of the original Raspberry Pi Pico, which is a significant advantage for users looking to upgrade existing projects.Β
Here is a breakdown of the pin functions for the Raspberry Pi Pico 2:Β
Power PinsΒ
The board provides several pins for power input and output, offering flexibility for different project needs.Β
- VBUS (Pin 40): This pin is directly connected to the micro-USB port's 5V power supply. It can be used to power the board or to detect if USB power is present.Β
- VSYS (Pin 39): The main system input voltage, which accepts a range between 1.8V and 5.5V. This pin feeds the on-board power supply and is the recommended way to power the Pico 2 from an external source like a battery.Β
- 3.3V (Pin 36): A regulated 3.3V output generated by the on-board Switched-Mode Power Supply (SMPS). It can be used to power external sensors and modules that require a 3.3V supply.Β
- GND (Pins 3, 8, 13, 18, 23, 28, 33, 38): There are eight ground pins distributed around the board to ensure stable and reliable electrical connections for your circuits.Β
- EN (Pin 37): This pin acts as an enable for the 3.3V regulator. Pulling it to ground will disable the 3.3V output.Β
- ADC_VREF (Pin 35): Provides a stable reference voltage for the Analog-to-Digital Converter (ADC), which is crucial for achieving accurate analog readings.Β
GPIO and CommunicationΒ
The majority of the pins on the Pico 2 are multifunctional General-Purpose Input/Output (GPIO) pins, which can be configured for various roles.Β
- Digital I/O: The board features 30 GPIO pins, from GPIO0 to GPIO29, that can be used for general-purpose digital input and output.Β
- Communication Protocols: The Pico 2 is equipped with hardware for several standard communication protocols, and these functions can be mapped to different GPIO pins.Β
- I2C: Two I2C controllers (I2C0 and I2C1) are available for communicating with sensors and displays. For example, GPIO4 and GPIO5 can be used as SDA0 and SCL0.Β
- SPI: Two SPI controllers (SPI0 and SPI1) allow for high-speed communication with devices like SD card readers and certain screens. GPIO16-19 can form a complete SPI interface.Β
- UART: Two UART interfaces (UART0 and UART1) are available for serial communication, commonly used for debugging or connecting to GPS modules. GPIO0 and GPIO1 can be used as TXD0 and RXD0.
Analog, PWM, and System PinsΒ
- Analog Inputs (ADC): For reading analog sensors, the board offers three ADC channels accessible on the main header: GPIO26 (ADC0), GPIO27 (ADC1), and GPIO28 (ADC2).Β
- Pulse Width Modulation (PWM): Every GPIO pin on the board is capable of producing a PWM signal. The diagram shows that each pin is linked to two PWM channels (A and B), providing extensive control for tasks like dimming LEDs, controlling servo motors, or generating tones.Β
- RUN/RESET (Pin 30): This pin allows you to reset the RP2350 microcontroller without unplugging the board.Β
- Debug Port (SWD): For advanced users who need to debug code directly on the chip, the Serial Wire Debug (SWD) interface is available on three pads located on the bottom edge of the board (SWDIO, SWCLK/JTCK, and GND).Β
On-Board FunctionsΒ
Several GPIO pins are also connected to internal functions on the board itself.Β
- GPIO25: Connected to the on-board user-controllable LED, providing a simple way to give visual feedback.Β
- GPIO24: Used to sense if VBUS (USB voltage) is present.Β
- GPIO23: Controls the on-board SMPS power-saving mode.Β
- GPIO29: Used internally by the ADC (ADC3) to monitor the system voltage (VSYS).
Comparison Table
Here is a detailed comparison of their specifications:
| Feature | Raspberry Pi Pico 2 | Raspberry Pi Pico |
|---|---|---|
| Microcontroller | RP2350 | RP2040 |
| CPU Cores | Dual-core Arm Cortex-M33 or Dual-core RISC-V Hazard3 | Dual-core Arm Cortex-M0+ |
| Clock Speed | 150 MHz | 133 MHz |
| On-Chip SRAM | 520 KB | 264 KB |
| On-Board Flash | 4 MB | 2 MB |
| Security Features | Arm TrustZone, signed boot, hardware TRNG, SHA-256 acceleration | None specified |
| Programmable I/O (PIO) | 3 blocks (12 state machines) | 2 blocks (8 state machines) |
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Conclusion
The Raspberry Pi Pico 2 is a masterclass in evolution. It takes everything that made the original Pico a runaway successβits accessibility, flexibility, and low costβand elevates it to a new level.
By integrating the powerful RP2350 chip, Raspberry Pi has delivered a board that doesn't just keep pace with the growing demands of the embedded world but actively enables a new generation of more powerful, more secure, and more ambitious projects.Β
The substantial upgrades in processing power with the choice of Arm Cortex-M33 or RISC-V cores, the doubling of both SRAM and flash memory, and the introduction of a comprehensive, transparently documented security architecture are not just incremental improvements; they are transformative.
These features collectively shift the Pico 2 from being primarily a hobbyist and educational tool to a serious contender for professional and commercial applications, particularly in the burgeoning field of IoT.
