STMicroelectronics Adds Zigbee 3.0 Support for IoT Developers

By RFID Journal

The company has also introduced a new discovery kit and expansion software, and it has acquired UWB firm BeSpoon and the cellular IoT connectivity assets of Riot Micro.

STMicroelectronics has recently added Zigbee 3.0, based on the Zigbee PRO protocol stack support, to its STM32WB55 wireless microcontrollers. This, according to the company, will enable STM32 developers to leverage the interoperability and power-saving features of Zigbee networking for such projects as home automation, smart lighting, smart buildings and Internet of Things (IoT) connectivity.

Zigbee 3.0 combines the features of Zigbee specifications for consumer and industrial applications, which has driven many consumer and Internet brands to choose Zigbee connectivity for new smart-home products. A long-term supporter of Zigbee technology, STMicroelectronics is a member of the Zigbee Alliance's Board of Directors and a council member of the Zigbee Alliance Member Group China, and it supports the Connected Home Over IP (CHIP) Project.

ST's Zigbee 3.0 software for the STM32WB55 includes Exegin's Zigbee PRO protocol stack, provided free of charge and delivered and fully supported by ST. This stack is used in Exegin products certified as Zigbee Golden Units and is approved as a reference stack for use by test laboratories. To ease development, ST's offer supports 46 Zigbee 3.0 clusters that help users establish device capabilities; a further 21 clusters support legacy products.

"This is a milestone for the Zigbee Alliance," said Leslie Mulder, Exegin's president, in a prepared statement. "With the advent of ST's Zigbee 3.0 offering, Zigbee is reaching a new level of maturity, one that has the potential to cement its and ST's leadership roles in the IoT market." STM32WB55 microcontrollers also support Thread and Bluetooth 5.0, with over-the-air update capability. There are 10 STM32WB55 variants, the company reports, offering a choice of package styles and Flash density ranging from 256 kilobytes to 1 megabyte.

According to the company, additional variants scheduled to be introduced during the next quarter will offer developers greater flexibility to meet application performance and cost targets. The devices feature Arm's Cortex-M4 with Floating Point Unit, as well as DSP instructions and a memory-protection unit designed to enhance application security. Arm's Cortex-M0+ coprocessor, built to manage the integrated IEEE 805.15.4 radio and the MCU's cyber-protection features, ensures that real-time low-layer operations run smoothly, ST reports. The RF transceiver has a link budget of 106dB to ensure reliable connections over distance.

STMicroelectronics' microcontroller technologies, including radio balun circuitry, are intended to allow STM32WB55 devices to help designers meet tight power and size constraints in a wide range of IoT and wearable devices, ST explains. The system includes analog and system peripherals, as well as cyber-protection and ID features, such as secure firmware installation, customer key storage, hardware public key authority and cryptographic accelerators. Capacitive touch and LCD controllers simplify user-interface integration, the company adds.

The Zigbee 3.0 software is now included in the STM32CubeWB MCU package, which provides embedded software including low-layer APIs and hardware-abstraction layer drivers for STM32WB microcontrollers, as well as Bluetooth 5.0, Mesh V1.0, Thread libraries, FreeRTOS kernel, the FatFS file system and the STMTouch capacitive-sensing library. The STM32Cube ecosystem, through STM32CubeMonitor-RF for RF testing and STM32CubeMX for device configuration and code generation, facilitates development, according to the company.

In addition, STMicroelectronics has announced that its B-L4S5I-IOT01A STM32 Discovery kit is intended to address the software challenges faced by IoT node developers. The kit comes with a qualified port of FreeRTOS, integrated into the STM32Cube ecosystem and able to connect to Amazon Web Services.

The hardware includes an STM32L4+ microcontroller board that contains a selection of ST MEMS sensors, an STSAFE-A110 secure element, Bluetooth 4.2 and Wi-Fi modules, and an NFC tag with a printed antenna for flexible, low-power communication with cloud servers. Included with the X-CUBE-AWS v2.0 STM32Cube expansion pack, the kit can be used as a reference design to accelerate final product completion, according to STMicroelectronics.

The X-CUBE-AWS v2.0 pack ensures proper integration of the FreeRTOS standard AWS connectivity framework within the STM32Cube environment. This lets users utilize both FreeRTOS and STM32Cube without having to develop additional software. It supports AWS native services, including standard firmware OTA tasks, and handles interactions with the onboard STSAFE-A110 secure element. This includes taking care of AWS IoT Core multi-account registration and assigning security-critical operations during bootup, device authentication and OTA firmware verification.

ST says the STM32L4+ board is designed to meet the performance demands and energy constraints typically placed on IoT nodes. The STM32L4S5VIT6's Cortex-M4 microcontroller offers 2 megabytes of Flash, 640 kilobytes of RAM, digital and analog peripherals, and a hardware encryption accelerator. The onboard sensors include an HTS221 capacitive digital relative-humidity and temperature sensor, an LIS3MDL high-performance 3-axis magnetometer, an LSM6DSL 3D accelerometer, a 3D gyroscope, an LPS22HB absolute digital output barometer, a VL53L0X time-of-flight and gesture-detection sensor, and two digital omnidirectional microphones.

The B-L4S5I-IOT01A discovery kit can be ordered directly from ST or from its distributors. The X-CUBE-AWS v2.0 STM32Cube expansion pack can be downloaded free of charge.

Finally, STMicroelectronics has announced the signing of two agreements related to its acquisitions of the share capital of UWB specialist BeSpoon and of the cellular IoT connectivity assets of Riot Micro. The two transactions, subject to customary regulatory approvals, will strengthen ST's offer for wireless connectivity, the company reports—in particular, the roadmap for its STM32 microcontrollers and secure MCUs.

BeSpoon, based in France, is a fabless semiconductor company specializing in ultra-wideband communications technologies. Its solutions enable secure real-time indoor location with centimeter accuracy in environments under adverse conditions. The integration of this positioning technology in the STM32 product portfolio, according to ST, will enable developers of IoT, automotive and mobile communication applications to provide secure access and precise indoor and outdoor mapping. ST will acquire BeSpoon from its majority shareholder, TRUMPF, and from its founders. In parallel with the transaction, ST and TRUMPF will enter into a strategic partnership for UWB tracking technology.

Riot Micro, based in Canada, designs cellular IoT solutions by applying Bluetooth Low Energy and Wi-Fi to LTE Cat-M and NB-IoT. The integration of cellular communication capabilities into the STM32 portfolio will strengthen ST's offer for customers developing applications such as asset tracking, metering and fleet-management services, the company explains. The terms of the transactions have not been disclosed.

"At ST, we work to offer our customers the products and solutions they need in order to address their opportunities and challenges," said Claude Dardanne, the president of ST's Microcontrollers and Digital ICs Group, in a prepared statement. "Cellular IoT and UWB technologies are key wireless connectivity solutions that will enable a next wave of IoT-connected objects and innovative applications."

"These acquisitions complement ST's existing wireless microcontroller offer, which includes Bluetooth 5.0 and IEEE 802.15.4 communication protocols, as well as the world's first LoRa-enabled system-on-chip," Dardanne added in the prepared statement. "Wireless microcontrollers are part of our STM32 product offer of over 1,000 different devices and with over six billion parts shipped to customers. With these acquisitions, we will address all wireless IoT communication protocols."