The ARM Cortex-M4 is a 32-bit processor core licensed by ARM Holdings. It is part of the Cortex-M series of microcontrollers and is designed for embedded and IoT applications requiring low power consumption and high performance. The Cortex-M4 has a variety of features that make it well-suited for building prototypes and proof-of-concept designs.
A development board is a printed circuit board that is designed to aid in the development and prototyping of embedded systems using a particular microcontroller or processor. For the ARM Cortex-M4, there are many development boards available from various manufacturers. These boards integrate the Cortex-M4 MCU along with various peripherals and interfaces to facilitate rapid development.
Benefits of Using a Cortex-M4 Development Board
Here are some of the key benefits of using a development board with the ARM Cortex-M4 MCU:
- Rapid prototyping – Development boards allow engineers to quickly test and iterate on their designs without having to build a custom PCB.
- Pre-integrated interfaces – Common peripherals like USB, Ethernet, LCD displays, buttons, etc. are already wired up and ready to use.
- Debugging support – On-board debug probes and debug headers provide easy access for flashing code and debugging.
- Cost-effective – Development boards are much cheaper than building custom boards for initial development.
- Community knowledge – Since popular boards are used by many engineers, there is a lot of shared community knowledge available.
Key Features of Cortex-M4 Development Boards
Some of the common features found on many Cortex-M4 development boards include:
- Cortex-M4 MCU – This is the microcontroller chip itself. Popular options include STM32F4xx, NXP Kinetis K20/K60, TI Tiva TM4C123.
- Clock sources – On-board oscillators or support for external clock sources.
- Power supply – USB port, barrel jack or terminal blocks for power input.
- Debug interface – SWD header compatible with external debug probes.
- Connectivity – USB device/host ports, Ethernet, CAN, UARTs, SPI, I2C for connecting peripherals.
- User I/O – LEDs, buttons, buzzers for simple user interaction.
- Expansion headers – Allow connecting additional boards or breakout modules (Arduino form factor is common).
- Test points – For easy access to board signals when probing with an oscilloscope or multimeter.
Selecting a Cortex-M4 Development Board
With so many development boards to choose from, here are some key considerations when selecting one for your project:
- MCU model – Pick a board with your desired Cortex-M4 chip from vendors like ST, NXP, TI etc.
- Community support – Choose a popular board with strong user community and good documentation/examples.
- Hardware interfaces – Ensure required peripheral interfaces like USB, Ethernet, wireless, etc. are available.
- Form factor – Size, shape and layout that fits your use case and environment.
- Debugging support – On-board debug probe or SWD header to connect external debugger.
- Expansion capability – Headers to add functionality via plug-in modules.
- Development tools – Compatible toolchain and IDE for code development & debugging.
- Budget – Balance required features and capabilities with affordability.
Popular ARM Cortex-M4 Development Boards
Here are some of the most popular development boards used with the ARM Cortex-M4 processor:
STM32F4 Discovery Board
- STM32F407VGT6 microcontroller (168 MHz Cortex-M4)
- On-board ST-LINK/V2 debug probe
- LCD display, buttons, LEDs
- USB, Ethernet, CAN, audio interfaces
- Arduino and PMOD expansion connectors
- ST development tools and ecosystem
STM32 Nucleo-F4 Boards
- Multiple Nucleo-64 and Nucleo-144 board variants with different STM32F4 MCUs
- Arduino Uno V3 and ST morpho connectors
- On-board ST-LINK/V2-1 debugger
- USB, Ethernet, CAN options
- Open-standard form factor
NXP LPCXpresso4337 Board
- NXP LPC4337JBD144 (Cortex-M4/M0) MCU
- On-board LPC-Link2 debug probe
- Ethernet, USB Host/Device
- TFT display connector
- Arduino R3 expansion connectors
- NXP MCUXpresso development tools
TI Tiva C Series TM4C123G LaunchPad
- TM4C123GH6PM microcontroller (80 MHz Cortex-M4)
- On-board XDS110 debug probe
- USB, UARTs
- Booster Pack expansion connectors
- TI Code Composer Studio IDE
In addition to these, there are many other boards like the STM32F4 Discovery kit, STM32F769I Discovery Board, MikroElektronika STM32F4 Stamp Board, NXP FRDM-K64F Board, Particle Photon Board, etc. that can be used for developing with the Cortex-M4 processor.
Getting Started with a Cortex-M4 Development Board
The basic steps to get started with a new ARM Cortex-M4 development board are:
- Set up hardware – Connect the board to your PC using the USB port. External power supply may be needed.
- Install software tools – Download and install an IDE like Keil MDK, IAR EWARM, STM32CubeIDE etc. Add toolchain support for the MCU on your board.
- Install USB drivers – Required USB device drivers allow the IDE to recognize the board.
- Configure debug probe – Connect and configure the on-board debug probe or external debugger.
- Run demos – Build and run the simple demo applications provided for the board.
- Review documentation – Read the board’s quick start guide, user manual, schematics etc.
- Start coding – Create a new project, write code, debug and validate it on the device.
Keep the board’s documentation handy as reference material while programming. Leverage sample code provided to quickly gain experience. Consider joining forums and communities specific to the dev board for guidance and to find solutions to issues faced.
Typical Development Workflow
A typical embedded C/C++ development workflow using an ARM Cortex-M4 development board involves:
- Creating your application code in C/C++, built on the board support package libraries.
- Compiling the code to generate an executable binary file.
- Flashing the binary to the microcontroller memory via the debug probe.
- Debugging code by controlling execution and monitoring variables in runtime.
- Analyzing program execution to identify and fix issues.
- Repeating the edit-compile-download-debug cycle rapidly during development.
- Validating logic and functionality of your program on actual hardware.
- Measuring real-time performance like CPU load, memory usage, power consumption.
- Stressing your system by simulating different environments, error conditions, and edge cases.
With the quick turnaround time enabled by the development board and debug probe, you can comfortably make changes, experiment, build, and test your embedded software.
Conclusion
ARM Cortex-M4 development boards enable engineers to prototype, validate, and troubleshoot embedded designs quickly on actual hardware. With powerful debugging capabilities and easy access to peripheral interfaces, they provide an efficient way to build and fine-tune your embedded applications. Choosing a board with adequate community support and development tools is key for a smooth development experience. So get yourself a Cortex-M4 dev board and start building your next ARM-powered creation!