Mastering Portenta H7 with MicroPython

The Portenta H7 is a powerful and versatile development board by Arduino, designed for high - performance applications. MicroPython, on the other hand, is a lean and efficient implementation of the Python 3 programming language that includes a small subset of the Python standard library and is optimized to run on microcontrollers. Combining the Portenta H7 with MicroPython allows developers to leverage the simplicity and expressiveness of Python to quickly prototype and develop applications for the board. This blog post will guide you through the fundamental concepts, usage methods, common practices, and best practices of using MicroPython on the Portenta H7.

Table of Contents#

  1. Fundamental Concepts
  2. Getting Started
  3. Usage Methods
  4. Common Practices
  5. Best Practices
  6. Conclusion
  7. References

Fundamental Concepts#

Portenta H7#

The Portenta H7 is built around a dual - core STM32H747XI microcontroller. It features a Cortex - M7 core running at up to 480 MHz and a Cortex - M4 core running at up to 240 MHz. It has a rich set of peripherals including GPIO, SPI, I2C, UART, USB, and Ethernet, making it suitable for a wide range of applications such as industrial automation, robotics, and IoT.

MicroPython#

MicroPython is designed to be easily embeddable in microcontrollers. It provides a high - level programming interface, which means you can write code in Python instead of low - level languages like C or Assembly. This significantly reduces the development time and makes it accessible to a wider audience of developers.

Getting Started#

Prerequisites#

  • A Portenta H7 board
  • A USB cable
  • A computer with a compatible operating system (Windows, macOS, or Linux)

Installing MicroPython#

  1. Download the latest MicroPython firmware for the Portenta H7 from the official MicroPython website.
  2. Put the Portenta H7 into DFU (Device Firmware Update) mode. You can do this by holding down the BOOT0 button while pressing and releasing the RESET button.
  3. Use a tool like dfu - util (available on Linux) or the official Arduino IDE to flash the MicroPython firmware onto the board.

Connecting to the REPL#

Once the firmware is flashed, you can connect to the MicroPython REPL (Read - Evaluate - Print - Loop) using a serial terminal program like PuTTY (Windows) or Minicom (Linux). Connect the board to your computer via USB and open the serial port at the appropriate baud rate (usually 115200).

Usage Methods#

Blinking an LED#

The following code demonstrates how to blink an LED connected to a GPIO pin on the Portenta H7 using MicroPython:

import machine
import time
 
# Define the GPIO pin for the LED
led = machine.Pin(25, machine.Pin.OUT)
 
while True:
    led.on()
    time.sleep(1)
    led.off()
    time.sleep(1)

In this code, we first import the machine module, which provides access to the hardware resources of the board, and the time module for adding delays. We then define a Pin object for the LED and set it as an output pin. In the infinite loop, we turn the LED on, wait for 1 second, turn it off, and wait for another 1 second.

Reading an Analog Input#

The Portenta H7 has analog - to - digital converters (ADCs) that can be used to read analog signals. The following code reads an analog value from a pin:

import machine
 
# Define the ADC pin
adc = machine.ADC(machine.Pin(26))
 
while True:
    value = adc.read_u16()
    print("Analog value:", value)

In this code, we create an ADC object for a specific pin and then continuously read the analog value in the loop and print it.

Common Practices#

Using Interrupts#

Interrupts are a powerful way to handle events asynchronously. For example, you can use an interrupt to detect a button press:

import machine
 
# Define the button pin
button = machine.Pin(14, machine.Pin.IN, machine.Pin.PULL_UP)
 
def button_pressed(pin):
    print("Button pressed!")
 
# Attach the interrupt handler
button.irq(trigger=machine.Pin.IRQ_FALLING, handler=button_pressed)

In this code, we define a button pin and set it as an input with a pull - up resistor. We then define an interrupt handler function button_pressed and attach it to the button pin using the irq method. The interrupt is triggered on the falling edge of the signal.

Communicating with Peripherals#

The Portenta H7 supports various communication protocols such as SPI, I2C, and UART. Here is an example of using I2C to communicate with a sensor:

import machine
 
# Initialize I2C
i2c = machine.I2C(0, scl=machine.Pin(13), sda=machine.Pin(12), freq=400000)
 
# Scan for I2C devices
devices = i2c.scan()
if devices:
    for device in devices:
        print("Device found at address:", hex(device))

In this code, we initialize an I2C bus with specific SCL and SDA pins and a frequency of 400 kHz. We then scan for I2C devices on the bus and print their addresses if any are found.

Best Practices#

Memory Management#

MicroPython has limited memory on the Portenta H7, so it's important to manage memory efficiently. Avoid creating large lists or strings if possible, and use generators or iterators instead.

Error Handling#

Always use try - except blocks to handle errors in your code. This can prevent your program from crashing due to unexpected events such as hardware failures or incorrect input.

try:
    # Code that may raise an error
    adc = machine.ADC(machine.Pin(26))
    value = adc.read_u16()
except Exception as e:
    print("An error occurred:", e)

Modular Programming#

Break your code into smaller functions and modules. This makes your code more organized, easier to understand, and easier to maintain.

Conclusion#

Using MicroPython on the Portenta H7 offers a convenient and efficient way to develop applications for the board. With its high - level programming interface, you can quickly prototype and implement various features. By understanding the fundamental concepts, usage methods, common practices, and best practices outlined in this blog post, you can make the most of the Portenta H7 and MicroPython combination.

References#

2025-10