“Matter, Expanding Flexibility in IoT Device Development and Selection”

Smart Home Solutions Seamlessly Interconnected Design
Matter+SoM based augmentation via border router

The Internet of Things (IoT) is revolutionizing how we interact with our devices, the world, and even our homes.

Today's advanced smart homes include a number of intelligent devices, such as lighting, control panels, HVAC (heating, ventilation, air conditioning), and security systems.

However, each of these devices may have different manufacturers. As IoT accelerates, multiple connectivity standards are competing for the smart home market, with Bluetooth® Low Energy, Wi-Fi®, and Thread gaining a dominant position.

But even the most mainstream RF protocols are non-interoperable, making it difficult to design seamlessly interconnected smart home solutions.

■ Matter Introduction

To solve the interoperability problems designers and consumers face because of competing RF protocols, tech companies banded together through the Connectivity Standards Alliance (CSA) to develop a standard called Matter.

Matter can work with existing smart home technologies such as Thread, Wi-Fi, and wired Ethernet protocols by adding a unified application layer to the protocol stack.

This allows smart home devices to communicate with each other securely and reliably.

The Matter standard enables a more seamless interface between devices using different RF wireless protocols, providing greater flexibility and choice for designers and consumers.

■ Smart Home Project

The core device of a smart home is the router. A router provides access to the Internet, allows communication between devices forming different networks, and connects devices via Wi-Fi or wired Ethernet.

This article demonstrates how Matter can be integrated into an innovative smart home project designing an IoT border router using Microchip Technology’s SAMA5D27 evaluation kit.

The kit features a SAMA5D27 SoM1 (system-on-module) on a SAMA5D27 baseboard, which in turn houses a SAMA5D27 SiP (system-in-package).

The build is completed by creating a Linux distribution image with this SoM.

So, let’s see how the SAMA5D27 evaluation kit is put together, what is a SoM, and how integrating Matter into a SoM-based smart home solution can benefit you.

■ Implementing Matter Solutions Using a SoM-Based Approach

Integrating Matter into a Linux-capable embedded processor such as the SAMA5D27 SoM enables several benefits when implementing smart home solutions.

The use of Matter and SoM-based approaches is increasing as border routers. Border routers act as a gateway between the external Internet and the smart home network, and can register devices using Bluetooth wireless technology and implement a security layer to protect the internal network.

The SAMA5D27 evaluation kit features an Arm® Cortex®-A5 32-bit processor running at up to 500 MHz.

The processor is housed in the SAMA5D27 SoM1 (Figure 1). This SoM provides the A5 processor along with a set of peripherals, including:

- Arm® Cortex®-A5 processor with floating point and SIMD units
- Power management
- 1GB of DDR
- 64Mb QSPI flash
- 10/100BASE-T Ethernet PHY
- 103 I/Os. Connect these I/Os to the processor's I/O. Supports SPI, I2C, UART, CAN, SDIO, and analog-to-digital converter (ADC) interfaces.

▲Figure 1: Microchip Technology's SAMA5D27 SoM1 system-on-module (Source: Mouser Electronics)

■ What is SoM?

SoM is a rapidly growing technique that reduces development time and risk.

Basically, SoM can be said to be a board-level circuit that integrates specific system functions into a single module.

It includes power, clocking, volatile and non-volatile memories. It also separates I/O lines so that the SoM can be connected to a carrier card for a specific application.

SoM forms the core of the system, and the rest of the solution is developed around it. A well-designed SoM-based solution enables developers to do a number of things:

■ Benefits of using SoM

The biggest advantage of using SoM-based solutions is that it allows developers to reduce technical risks and increase the solution’s Technology Readiness Level (TRL).

Project teams can use the TRL to measure the maturity of the technology components in their systems, rating their readiness for deployment on a scale of 1 to 9, with 9 being the most mature and least risky.

Using SoM provides developers with a TRL 5 solution. The SoM vendor designs, tests, verifies, and sells the SoM. Therefore, developers can focus on carrier card design to add value.

Along with the physical hardware, SoM vendors provide tools to support development. These include a Linux operating system, schematics, user guides explaining how to design the SoM onto a carrier card, and example projects and designs that can be used for development.

Developers can also significantly reduce project development time by using commercially available SoMs, as they can start development work from the beginning using SoMs. They can use application circuits with higher TRL levels, which reduces total engineering costs. Since SoMs provide proven designs, they require less software work.

Using an approach based on Matter and SoM also has an advantage in terms of marketing. It allows you to enter the market ahead of others, dominate the market, and achieve higher profits. This also allows developers to plan for next-generation products or field upgrades to currently deployed equipment sooner.

■ Development Board

Microchip Technology offers an evaluation kit to help developers evaluate and quickly jump-start their development with the SAMA5D27 SoM1. The evaluation kit features the SoM1 on a baseboard, along with a number of peripherals that allow developers to evaluate the SoM1’s capabilities. These include:

- Ethernet
- Digilent Pmod™ interface
- SD card
- 2 mikroe Click™ sockets. Communication possible via SPI, I2C, PWM, serial interface.
- Debug
- General purpose I/O
- USB
- CAN

It also provides debugging capabilities via an onboard J-Link debugger that can be connected via USB. Providing these peripherals allows developers to reduce the risk of developing applications.

■ Operating System

To get the most performance out of your hardware, you need an operating system (OS), in this case Linux. You can easily compile and build your OS of choice into SoM1 using popular Linux distributions like Ubuntu or OpenThread.

The first thing to do is to use a Linux machine or virtual machine. You can clone the required source code here:

- at91bootstrap bootloader
- U-Boot second stage bootloader source
- Ubuntu source

This will build the Ubuntu kernel and bootloader. You will also need to include a Linux file system (commonly called rootfs) and a device tree describing the processor and peripherals of the SoM1 and the configuration of the development board in your OS image.

Using the build artifact and rootfs, this image can be written to a partitioned SD card. After writing the image to the SD card, it can be used to boot the SoM1 and log in with an Ubuntu Linux distribution booting. Once logged in, the user can start developing the target application. This could be a simple "hello world" or a complex IoT border router for smart home applications that use Matter.

■ Matter Standard Integration

Once the operating system is customized and built into the SoM, the development team can build applications. Bluetooth wireless technology is used for device registration. So Wi-Fi and Ethernet can be used for high-bandwidth applications. Thread can be used as a mesh network for low-bandwidth communication. The source for building Matter is available on GitHub. Once the OS is running on the SoM, developers of smart home solutions can begin their development.

■ Conclusion

The Matter standard was developed to overcome the interoperability problems faced by designers and consumers due to different RF protocols in the smart home. Matter enables seamless communication between devices using different wireless protocols, thus providing designers and consumers with greater flexibility and choice. Integrating Matter into a Linux-capable embedded processor, such as the SAMA5D27 SoM1, enables many benefits when developing smart home IoT border router solutions. Using an SoM-based approach minimizes technical risk, increases TRL, reduces development time and effort, and from a marketing perspective, enables time to market, market share, and higher revenue.

※ Contributor
Written by: Adam Taylor

Courtesy of Mouser Electronics

Adam Taylor is an embedded systems professor, engineering leader, and internationally recognized expert on FPGAs/systems-on-chip and electronic design.