Despite slowdowns and shortages, there are several useful microcontrollers and microcontroller boards available as of the Spring of 2021.
As with SBCs (single board computers), CPUs, GPUs, and other electronics on the market, microcontroller production has been impacted by the pandemic, leaving manufacturers with limited resources. That being said, the chip shortage is expected to end in the coming months, with replenished supplies following shortly after. Regardless of said shortage, manufacturers have released many new microcontrollers before the pandemic, along with some new revisions to popular platforms. In this roundup, we will take a look at some of the best microcontrollers and microcontroller boards for 2021.
1: Groboards Giant Board
Groboards’ Giant Board is a tiny microcontroller based on the Adafruit Feather form factor with FeatherWing support. It packs a Microchip SAMA5D2 ARM Cortex-A5 processor with 128Mb of DDR2 RAM and a micro-SD card slot. The microcontroller also comes equipped with 6X 12-bit ADC with 3.3V reference and external trigger, 4X 16-bit PWM with an external trigger and I2C, SPI, and UART. Moreover, it’s powered via USB, offers support for LiPo batteries, and can run full Debian and take advantage of Adafruit Blinka (CircuitPython for Linux).
2: Seeeduino XIAO
Seeed Studio’s XIAO is one of the most miniature boards to support the Arduino architecture and comes embedded with a SAMD21G18 chip, which packs an ARM Cortex-M0+, 32Kb of SRAM, and 256Kb of Flash. I/O includes 14X GPIO, 11 analog, 11 digital, a single DAC output pin, and I2C, SPI, and UART. Power and programming are handled by a USB Type-C connection and features a series of LEDs for status and user programming. The XIAO Seeeduino also comes equipped with a pair of reset buttons (short connect to reset) and is fully compatible with the Arduino IDE.
3: The BBC micro:bit V2
The BBC micro:bit V2 is an improved version of the original microcontroller, which now includes a speaker and microphone, as well as several other enhanced features. The V2 packs a Nordic nRF52833 processor, 512Kb of Flash, 32Kb of RAM, and an NXP KL27Z interface chip. The tiny board also packs a 5 X 5 LED matrix, status LEDs, MEMS-based microphone/speaker, touch-sensitive logo, and user-programmable buttons. The V2 also features a 25-pin edge connector, 4X GPIO, PWM, I2C, SPI, and several ring pins for connecting alligator clips and holes for banana plugs. Wireless includes 2.4GHz RF and Bluetooth 5.1/BLE. The board also comes equipped with several sensors, including an accelerometer, thermometer, and electronic compass.
4: Adafruit Gemma M0
Adafruit’s Gemma M0 is about the size of a quarter and is designed as a wearable electronics platform that can be utilized for everything from cosplay to biomonitor. The tiny microcontroller is outfitted with an ATSAMD21E18 32-bit Cortex M0+, with 256Kb of Flash and 32Kb of RAM. The board also comes equipped with a DotStar RGB LED and several large sew-holes, which can be used with conductive thread or alligator clips, depending on the project. Each I/O pad can also be used as a 12-bit analog input or digital input/output and can even be used as hardware-capacitive touch sensors. According to Adafruit, the Gemma M0 can drive NeoPixels or DotStars and has enough memory to power over 8,000 pixels.
5: Arduino Uno Rev3
The Arduino Uno has been around for the better part of a decade in one form or another and is used as the foundation for many great projects. The latest board, Arduino Rev3, uses an ATMega328p microcontroller, with 32Kb of Flash, 2K of SRAM, and 1K of EEPROM. The board packs 14X digital input/output pins (6 can be used as PWM outputs), 6X analog inputs, a 16 MHz ceramic resonator (CSTCE16M0V53-R0), a USB connecter, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; users connect it to a computer with a USB cable or power it via an AC-to-DC adapter or battery to begin building their projects.
6: Adafruit Industries ESP8285
Espressif Systems ESP8285 microcontroller has been implemented in many aftermarket boards and has been an excellent chip for many projects. Adafruit’s ESP8285 is one of the more popular boards to be utilized and comes packed with a Wi-Fi front-end (as a client and access point) and TCP/IP stack. The chip also integrates antenna switches, RF balun, power amplifier, low noise receive amplifier, filters and power management modules. The ESP8285 also features an enhanced version of Tensilica’s L106 Diamond series 32-bit processor and on-chip SRAM, with 1Mb of Flash. Adafruit’s offering comes preprogrammed with the NodeMCU Lua firmware, so it’s ready to go right out of the box.
7: MPLAB PICkit 4 In-Circuit Debugger
Microchip’s MPLAB PICkit 4 is a portable in-circuit debugger with Programmer-to-Go functionality for 8-bit, 16-bit and 32-bit PIC MCUs, dsPICs, as well as SAM MCU devices via the integrated MPLAB X Integrated Development Environment (IDE). The kit is driven by a SAME70 MCU and supports many interfaces, including 4-wire JTAG and Serial Wire Debug with streaming Data Gateway. It’s also backward compatible for demo boards, headers and target systems using 2-wire JTAG and ICSP. As mentioned earlier, the PICkit 4 also has a Programmer-to-Go function that allows users to program different project codes and voltages, which can be saved with an onboard micro-SD card slot. Moreover, the debugger can be powered by the target board, making it easy to use in the field.
8: PJRC Teensy 4.1
PJRC’s Teensy 4.1 is the latest version of the widely used development board, which is purported to be 10X faster than the Teensy 3.1. The latest iteration sports an ARM Cortex-M7 (@ 600MHz), 7936K of Flash, 1024K of RAM, and 4K of EEPROM (emulated). It also packs 55X digital I/O pins, 18X analog inputs, 8X serial, 3X SPI, and 3X I2C ports. Additional features include 2X I2S/TDM and 1 S/PDIF digital audio port, 3X CAN bus, Ethernet (10/100M-bit), 32X general purpose DMA channels, and onboard RTC for date and time. What’s more, it also includes cryptographic acceleration, a random number generator, peripheral cross triggering, and power on/off management.
9: NodeMCU V2
The NodeMCU V2 is an open-source development platform based on the ESP8266 microcontroller. This is another popular chip for IoT projects and packs an ultra-low-power UART 802.11b/g/n Wi-Fi module for wireless connectivity. The board integrates a built-in TCP/IP protocol stack for up to five client connections. It features an onboard PCB antenna with a 2.54 in-line package, allowing users to debug equipment or direct product applications. The board also uses a Nodejs-style network API for event-driven network applications, speeding up IoT application development. It also packs a 10-pin GPIO that allows users to denote every pin as PWM, I2C, IIC, ADC, or 1-wire, depending on the application.
10: Microchip CEC1712 Cryptographic Controller
Microchip Technologies is known for its PIC and SAM-based MCUs, but the company also produces other microcontrollers, including those for cryptographic security. The company’s CEC1712 Cryptographic Controller packs an Arm 32-bit Cortex-M4 with Secure Boot and hardware Root of Trust (RoT) protection in a pre-boot mode for operating systems booting from SPI Flash. The bootloader loads, decrypts and authenticates firmware and applications before they are loaded into the operating system, ensuring the embedded system doesn’t become compromised. The chip uses Soteria-G2 firmware, which simplifies risk reduction during development by tasking the CEC1712 immutable secure bootloader (ISB), implemented in Read-Only Memory (ROM), as the system root of trust.
This article was originally published on EE Times.
Cabe Atwell is an electrical engineer living in the Chicago area.