Technical University "Gh.Asachi" Iași - Faculty of Automatic Control and Computer Science
Microprocessor Systems
Experiment 10+
  • L10+.1 Title

    • Raspberry Pi Pico - Pulse Matrix
  • L10+.2 General presentation, purpose

    • The laboratory experiment aims at interfacing analog sensors to Raspberry Pi Pico platforms as well as devices capable of communicating with the SPI protocol. The involved hardware resources are explored as well as the programming facilities offered by MicroPython for Raspberry Pi Pico/2. The concrete example refers to the development of an extension based on the MAX7219 controller for 8x8 LED matrices, a pulse sensor as well as a thermistor connected to the analog-to-digital inputs of the Pico platform. At the end of the laboratory you will have detailed information about the implementation and programming of digital extensions for ARM CortexM0 - Pico with the SPI protocol, as well as about acquiring information from analog sensors intended for the

    TinyML universe.


  • L10+.3 Resources


    • Hardware: Pico development platform, breadboard, 8x8 LED matrix with MAX7219 controller, 10K thermistor, pulse sensor, oscilloscope.

    Software: MicroPython + Thonny




  • L10+.4 Example programs


    • Micropython library module for MAX7219.

    1. Pulsating image
    2. Display pulse sensor data
    3. Display temperature sensor data - thermistor
    4. Matrix display with Max7219 library

  • L10+.5 How to conduct the laboratory

    • The SPI protocol uses synchronous serial transmission, the main signals used are shown in the figure below.

    PicoW is an extension of the Pico platform with WiFi and BT interface of type Infineon CYW43439. The Pico development platform has SPI interfaces whose signals are distributed to the extension pins according to the representation in the following figure:



    According to the documentation of the LED matrix with Max7219 controller it has an SPI interface through which it can be interconnected to the PicoW as shown in the following schematic:



  • L10+.6 Proposed problems


    • 1. Create a triangle/rectangle with adjustable visual intensity;
    2. Develop a solution for displaying alphanumeric characters;
    3. Develop a solution for creating a 4-digit display.
    4. Create a terminal that will display the numbers sent via BT from the mobile phone;
    5. Develop a display with IP;


  • L10+.7 The laboratory can be extended to:

    • Designing wearable computing devices
    • Developing applications based on sensor networks powered by energy harvested from the environment;
    • Developing the "intelligent cloud" universe
    • Creating intelligent 'light' processing units
    • Industrial/medical/educational applications


    The Micro:bit is supported by the ELL framework which originated from Microsoft.
  • L10+.8 Additional information
    • © 2025 - Fl. Pantilimonescu, Technical University Iași, Romania