🛠 Advanced I/O Integration on the Smart Display Module

Objectives

This guide is intended for experienced developers looking to leverage the Input/Output (I/O) capabilities of the Raspberry Pi Smart Display Module. Unlike standard boards, this module is designed for cable-free integration, which complicates access to physical GPIO pins. The goal is to understand how to access available signals via internal connectors or specific adapters to connect environmental sensors or actuators for interactive signage applications.

Required Hardware

• A Raspberry Pi Compute Module 5 installed in the Smart Display Module.
• A professional SDM-compatible display connected to the module.
• An adapter or baseboard allowing access to GPIO pins (the module alone does not expose standard pins).
• An I2C or GPIO-compatible sensor (e.g., temperature sensor or push button).
• Connecting cables (Dupont) if a GPIO adapter is used.
• Stable power supply for the entire system.

Steps

The Smart Display Module is optimized for video and power via the SDM connector. For I/O, you must use the GPIO pins of the Compute Module 5. Check the technical documentation to identify pins accessible via the base connector or a specific adapter. Note that space is limited and heat dissipation must be managed.

1. Identify Available Interfaces

Ensure your Raspberry Pi OS is up to date and GPIO interfaces are enabled. Open a terminal and run: ``bash sudo apt update && sudo apt upgrade -y sudo raspi-config ` Navigate to Interface Options and enable I2C or SPI` depending on your sensor.

1. Configure the Operating System

Connect your sensor to the identified GPIO pins. For example, for an I2C sensor, connect SDA and SCL to the corresponding GPIO pins (typically GPIO 2 and 3 on standard Pi models, but verify the exact mapping for the CM5). Ensure voltage compatibility (3.3V).

1. Physical Wiring

Install the necessary tools to interact with GPIOs: ``bash sudo apt install python3-gpiozero python3-smbus -y ``

1. Install Libraries

Create a Python script to read sensor data. Example for a GPIO button: ```python from gpiozero import Button from time import sleep

1. Write the Test Script

button = Button(4)

while True: if button.is_pressed: print("Button pressed") sleep(0.1) ```

Verification

Run the script with python3 script.py. Press the button or expose the sensor to a physical change. If data appears in the terminal, the I/O link is functional. Also, verify that the 4K video display is not disrupted by electrical interference.

Further Reading

Explore using the M.2 port to add an AI accelerator like the Hailo, enabling local processing of sensor data for intelligent signage.