Meeting Modern Connectivity Requirements With Cloud Authentication and Diverse Communication Capabilities

Abstract

In the landscape of modern electronics, everything is connected. This includes internal-connected MCUs, sensors, controllers and peripherals, as well as external connections with wireless communication and cloud services. The diverse range of con-nectivity and communication standards and technologies is often a puzzling mix to designers and developers of embedded systems. With more emphasis on embedded security, there is now another layer of complexity added to external and internal communications, which are not allotted any additional power in Internet of Things (IoT) or wireless sensor applications. 

This new age of universal connectivity has created a need for simple and secure solutions to connect to the cloud within a variety of embedded applications. This article strives to communicate the latest considerations and challenges faced by embedded designers working with embedded connectivity and communication technologies, specifically those driven by Digital Signal Controllers (DSCs), Microcontrollers (MCUs) and Microprocessors (MPUs). Furthermore, this article will describe how Microchip’s hardware solutions, software tools/resources and new cloud-enabled development boards and devices can help designers and developers hit shrinking product develop cycle goals with competitive features and reliable security technologies.

Emerging Connected Applications Grow Alongside New Design Challenges

For embedded applications, internal connectivity and external communication are designed and optimized to facilitate data and signal exchange between system components, devices, network infrastructure, processing units and storage units. Hence, the requirements for a connectivity or communication function are dictated by the applications they serve. The dominant applica-tions are reliably connecting local and cloud-based intelligence to distributed sensors, actuators and controllers with low latency and high-power efficiency, in small, upgradable assemblies that ensure security, all while being easily integrated and developed for a wide range of applications. Emerging connected car, artificial intelligence, smart sensors, intelligent edge/intelligent mesh and the new data economy are major influencing factors on the types and amounts of data being captured and communicated. With a myriad of requirements, there also needs to be a diverse selection of connectivity and communication options to serve these various applications. 

This is not always an easy or straightforward goal to meet with most DSCs, MCUs and MPUs, which are usually limited in integrated connectivity and communication peripherals. Moreover, adding external peripherals typically increases BOM complexity, leads to larger system footprints, requires more complex and sometimes high-speed data lines along with PCB layers and layout, reduces power efficiency, makes systems more susceptible to interference and can even introduce security vulnerabilities. 

Another note is that common connectivity and communication interfaces, such as USB and Ethernet, are generally difficult and expensive to implement as external peripherals. The additional timing, RAM and other supporting hardware necessary to implement USB and other high-speed data connectivity and communication technologies also tends to add to the complexity and cost of IoT and automotive electronics. On top of these other challenges is the sometimes nebulous and often painstaking process of ensuring secure connections between embedded devices and cloud services.

Modernized DSCs/MCUs/MPUs With Diverse Integrated Peripherals and Design Features to Tackle the Connected World

One method of reducing BOM cost/complexity, PCB routing complexity, footprint, power consumption and design time is to leverage DSCs, MCUs and MPUs with integrated peripherals and features that eliminate the need for additional external components and connectivity. In prior years, there was only a limited selection of devices with a limited number of integrated peripherals and designers/developers needed to prototype and test each additional peripheral they needed for their designs. This required balancing communications amongst a relatively small number of serial interfaces, UARTs and GPIO pins, which may not necessarily have been capable of the desired speed and reliability for key applications, such as automotive.

Now there are embedded devices available that integrate a wide range of peripherals and include many features that help to reduce the design and development complexity while enhancing power efficiency and other performance aspects. This integration of peripherals can be augmented in value if they are Core Independent Peripherals (CIPs), which can complete operations with-out burdening, or even waking, the CPU and reduces overall power consumption. Key among these integrated peripherals are connectivity and communication interfaces and the protocols the embedded devices support. For example, USB is a common hurdle that must be overcome for many embedded applications. As the timing requirements for a USB interface are so stringent, an onboard crystal oscillator and associated circuitry are required to maintain the timing accuracy. Microchip has addressed this challenge by offering a wide range of MCUs (8-/16-/32-bit MCUs) and 16-bit DSCs with integrated USB interfaces, some of which are capable of timing accurate enough to remove the need for an external crystal oscillator and are USB OTG-capable.

Many of Microchip’s USB MCUs/DSCs are also augmented with many additional connectivity and communication peripherals, including common motor control and automotive protocols. This includes several 16-bit DSC and 32-bit MCU families that feature integrated CAN, CAN FD, SENT, LIN, AUTOSTAR and even 8-bit MCUs that support CAN and lighting protocols such as DALI and DMX. The MCUs and DSCs that support automotive and industrial protocols also sport standards-compliant functional safety features that ease compliance as well as high-temperature operation, which enable their use in safety-critical industrial and automotive applications. 

Some communication protocols, especially in those for automotive applications such as AUTOSAR, tend to require significant amounts of Flash storage and RAM. Hence, Microchip’s solutions that support these protocols also feature the necessary integrated storage and memory to support these protocols, among others. Other compatible protocols and interfaces include TCP/IP, UARTS, I2C, SPI and others. TCP/IP protocols are rather complex, and Microchip provides turn-key TCP/IP libraries for each compatible MCU.

Beyond wired connectivity, the next generation of communication devices is increasingly turning to wireless connectivity, either to connect to the internet/cloud, between hosts/controllers or to each other through direct communication or mesh networking. Among the most common wireless communication technologies for embedded devices are Wi-Fi®, Bluetooth®, IEEE 802.15.4 (zigbee®) and LoRa, along with other assorted ISM-band and unlicensed RF communications. 

As most embedded developers aren’t RF engineers, external wireless modules are the most common way wireless communication is implemented. Microchip offers a wide range of wireless modules, as well as space, time, and cost-saving MCUs with inte-grated wireless communication capabilities. Among these integrated solutions are complete Wi-Fi modules, Bluetooth MCUs, IEEE 802.15.4 MCUs, LoRa MCUs, and a wide range of unlicensed and ISM-band integrated MCUs. Leveraging these highly integrated wireless communication MCUs helps to save power, reduce design complexity, and accelerates time-to-market, which is essential in the highly competitive and rapid-paced IoT and smart home marketplace.

Cloud Partnerships Accelerate Time-to-Market and Simplify Security

Cloud services can greatly augment the capabilities, and value, of an IoT or smart home device. For instance, cloud services could enable enhanced features using machine intelligence, user customization/control, Over-the-Air (OTA) updates, notifications, real-time analysis, among many more. However, incorporating the communication hardware and networking capability that enables these features also opens an untold number of avenues for malicious tampering or even information theft. Securing embedded devices, wireless and wired, has become a major focus of OEMs, as customers are increasingly demanding better security to protect their personal data and ensure their IoT devices operate reliably.

With this in mind, Microchip engineers have partnered with several leading cloud services to provide IoT modules and em-bedded devices that simplify IoT security and reduce the time-to-market for the current generation and next generation of IoT devices. In particular, this includes IoT development boards, kits, and devices that work with Google’s IoT Core, Amazon Web Services, Microsoft Azure, and The Things Industries Join Servers for LoRa authentication. The above includes a Microsoft-certified Azure IoT Starter Kit for rapid development, and an IoT Development kit that supports both Device Identifier Composition Engine (DICE) and Azure IoT Hub Device Provisioning Services (DPS).

The AVR-IoT WG and PIC-IoT WG Development boards are a quick way to start for developing applications using Google IoT Core and incorporate either an 8-bit ATmega4808 or PIC24FJ128GA705 MCU, fully certified ATWINC1510 Wi-Fi network controller, and an ATECC608A CryptoAuthentication™ secure element IC. The above combine to form a board that requires no additional hardware to program and debug, and the preloaded firmware image enables instant setup and communication with the Google Cloud IoT platform. Both Wi-Fi enabled development boards are compatible with MPLAB® X IDE and can be programmed easily with the freely available Atmel Start and MPLAB Code Configurator (MCC). Additionally, the ATECC608A CryptoAuthentication IC can be integrated with other designs and enables the same secure services as with the AVR-IoT and PIC-IoT development boards, which makes it an excellent tool for exploring and prototyping Google IoT Core applications.

Moreover, the ATECC608A IC is also compatible with Amazon AWS IoT Core and can be used to enable Zero Touch Provisioning (ZTP) for AWS IoT devices. ZTP means that IoT devices can be pre-provisioned with AWS cloud services at Microchip’s secure facilities and that no security keys can be exposed externally. With ZTP, OEMs also don’t have to build secure infrastructure for provisioning devices, saving time and money when deploying IoT devices and services. Furthermore, AWS also offers IoT Greengrass Hardware Security Integration as part of the IoT Greengrass Core software, which can be used as a microprocessor-agnostic security solution for true hardware secure key storage for any Linux®-based IoT product. There is also a ZTP kit version for AWS IoT, or a socketed AT88CKSCKTUDFN-XPRO add-on board can be used with other Microchip development boards to allow for fast prototyping and testing of IoT services.

Conclusion

In the multiplex world of IoT, smart homes and connected automotive electronics, there is a distinct lack of simple solutions. The diversity, competition, and variability of these growing markets almost guarantee a high level of complexity, and a substantial design and development burden when building solutions for these markets. An area that poses some of the most significant challenges for these solutions is connectivity and communications features. Microchip DSCs, MCUs and MPUs with integrated connectivity interfaces and communications modules, including the new IoT cloud-ready solutions, go a long way in easing designer and developers challenges with deploying solutions that are power-efficient, reliable, secure and can be released to market in time to be viable and profitable.