solderic.com The RP2040 offers dual-core ARM Cortex-M0+ processors running at 133 MHz with abundant GPIO pins and built-in programmable I/O, providing excellent performance and flexibility for embedded projects compared to the SAMD21's single-core Cortex-M0+ at 48 MHz designed for low-power applications. Discover how these differences impact your development choices and which microcontroller suits your specific needs by reading the rest of this article.
Comparison Table
| Feature | RP2040 | SAMD21 |
|---|---|---|
| Manufacturer | Raspberry Pi Foundation | Microchip Technology |
| Core | Dual-core ARM Cortex-M0+ | Single-core ARM Cortex-M0+ |
| Clock Speed | Up to 133 MHz | 48 MHz |
| Flash Memory | External QSPI Flash (up to 16 MB) | Up to 256 KB internal Flash |
| SRAM | 264 KB internal SRAM | 32 KB internal SRAM |
| GPIO Pins | 30 multi-function GPIOs | Up to 32 GPIOs |
| Interfaces | UART, SPI, I2C, PWM, PIO | UART, SPI, I2C, PWM, ADC, DAC |
| ADC Channels | 3 x 12-bit ADC | 6 x 12-bit ADC |
| DAC | No | 1 x 10-bit DAC |
| Power Consumption | Low power, depends on workload | Low power, optimized for battery use |
| Typical Applications | Performance-oriented embedded projects, dual-core multitasking | Low power, simple embedded applications |
Introduction to RP2040 and SAMD21
The RP2040 microcontroller by Raspberry Pi features a dual-core ARM Cortex-M0+ processor running at 133 MHz, providing high performance for embedded projects. The SAMD21, developed by Microchip, is based on a single-core ARM Cortex-M0+ processor clocked up to 48 MHz, known for its low power consumption and extensive peripheral support. Your choice between RP2040 and SAMD21 depends on required processing speed, power efficiency, and available development resources.
Key Features Comparison
The RP2040 microcontroller features a dual-core ARM Cortex-M0+ processor running at 133 MHz, 264KB of SRAM, and supports flexible I/O with Programmable I/O (PIO) state machines for custom peripheral interfaces. In contrast, the SAMD21 offers a single-core ARM Cortex-M0+ processor at up to 48 MHz, with 32KB to 256KB of flash memory and integrated analog features like a 12-bit ADC and DAC for enhanced sensor interfacing. RP2040 excels in raw processing power and I/O flexibility, while the SAMD21 provides lower power consumption and more integrated analog peripherals suitable for sensor-driven applications.
Microcontroller Architecture
The RP2040 microcontroller features a dual-core Arm Cortex-M0+ architecture running at 133 MHz, offering high performance and efficient power consumption. In contrast, the SAM D21 is built around a single-core Arm Cortex-M0+ processor operating at up to 48 MHz, prioritizing low power and peripheral integration. The RP2040's dual-core design provides parallel processing capabilities, while the SAM D21 emphasizes a rich set of on-chip peripherals for versatile embedded applications.
Processing Power and Performance
The RP2040 features a dual-core ARM Cortex-M0+ processor running at 133 MHz, delivering higher processing power compared to the SAMD21's single-core ARM Cortex-M0+ running at up to 48 MHz. This results in enhanced multitasking capabilities and faster execution for complex applications on the RP2040. The RP2040's larger on-chip SRAM of 264 KB also contributes to improved performance over the SAMD21's 32 KB SRAM, enabling more efficient data handling and buffer management.
Memory and Storage Capabilities
The RP2040 microcontroller features 264KB of on-chip SRAM and relies on external flash memory, typically supporting up to 16MB for program storage, enabling flexible and expanded application development. The SAMD21 offers 32KB to 256KB of flash memory and 4KB to 32KB of SRAM integrated on-chip, providing a balanced memory structure suited for moderate resource requirements. RP2040's external flash support allows for larger storage capacity compared to SAMD21's fixed internal flash, affecting program size and data handling capabilities.
Connectivity and Peripheral Support
The RP2040 microcontroller offers robust connectivity options, including USB 1.1 full-speed device support and flexible I2C, SPI, and UART peripherals, making it ideal for versatile embedded applications. The SAMD21, on the other hand, integrates a native USB 2.0 full-speed device with a USB interface and additional connectivity features such as CAN and I2S, providing enhanced communication capabilities for complex projects. You can choose the RP2040 for straightforward peripheral use or the SAMD21 when advanced connectivity and multimedia support are critical.
Power Consumption and Efficiency
The RP2040 microcontroller offers higher power efficiency with a typical operating current of around 30mA at 133 MHz, while the SAMD21 consumes approximately 2.9mA at 48 MHz in active mode but excels in ultra-low power sleep modes with consumption as low as 1.7 uA. Your choice depends on whether you prioritize processing power or minimal energy use; the SAMD21 is optimized for battery-powered applications requiring low wake-up currents, whereas the RP2040 provides a powerful dual-core ARM Cortex-M0+ processor that balances performance and power consumption. Both microcontrollers support various power-saving modes, but the SAMD21's advanced sleep states make it more suitable for extended battery life in IoT devices.
Development Tools and Ecosystem
The RP2040 microcontroller benefits from robust development tools including the official Raspberry Pi SDK and strong support in popular IDEs like Visual Studio Code and PlatformIO, fostering a vibrant community and extensive open-source libraries. In contrast, the SAMD21 offers mature tooling with Microchip's Atmel Studio, comprehensive MPLAB ecosystem, and broad integration into Arduino IDE, making it accessible for both professional and hobbyist developers. Your choice between these chips can hinge on the preferred development environment and the availability of ecosystem resources tailored to your project requirements.
Popular Use Cases and Applications
The RP2040 microcontroller is widely used in hobbyist projects, educational platforms, and DIY electronics due to its dual-core ARM Cortex-M0+ and cost-effective design, making it ideal for robotics, sensors, and IoT devices. The SAMD21, featuring a single-core ARM Cortex-M0+ and robust low-power performance, is favored in wearable tech, medical devices, and industrial automation where power efficiency and reliable peripheral support are critical. Your choice between RP2040 and SAMD21 should align with the specific application requirements, such as processing power versus low energy consumption.
Price and Availability
The RP2040 microcontroller offers a highly competitive price point, often under $1.50, making it an affordable choice for budget-conscious projects. It is widely available through numerous distributors and supported by a growing ecosystem, which ensures steady supply and ease of procurement. In contrast, the SAMD21 generally commands a higher price, around $3 to $5, and may face occasional availability issues due to semiconductor supply constraints.
rp2040 vs samd21 Infographic
