Wireless networking drives our modern world, whether through cellular, Wi-Fi, or emerging standards like LoRaWAN and Sigfox. Another technology that’s become ubiquitous over its 20 years of existence is Bluetooth. On a consumer level, you know this tech as what pairs earbuds to your phone and other one-to-one connected gadgets. Innovation has continued on this standard to allow for broadcast beacons that are useful for information and indoor telemetry transmission. Now the standard has expanded even further, adding mesh networking capabilities that allows for many-to-many communication, passing data from one device to another and back.
This mesh technology is specified to support up to a staggering 32,000 nodes per network and is currently implemented with over 1,000. It also allows for fast communication with government grade encryption to keep data secure. While this is a new facet to Bluetooth, the underlying tech has been proven over many years, giving it some assurance that it will be supported for years to come after you’ve implemented it in your design.
While that sounds exciting, the question then becomes how do you get started working with BT mesh? For that purpose, Cypress Semiconductor has the answer in the form of not one, but two evaluation kits, the CYW20819 board, and the CYBT-213043-MESH EZ-BT 4-board kit.
CYW20819 Ultra-Low-Power Bluetooth 5 MCU Evaluation Kit
The CYW20819 kit features the CYW920819EVB-02 Bluetooth module, complete with PCB antenna and an external antenna connector that can be used if needed. This module is Bluetooth 5 ultra-low power certified and can transmit at an extended data rate. Perhaps most importantly, it’s also Mesh 1.0 certified, meaning that it can implement flood-based messaging where data are passed from node to node for advanced IoT functionality.
This wireless board is permanently affixed to the larger carrier board, which forms the vast majority of the package’s physical bulk. It features a micro USB connector for power and programming, and usefully implements an Arduino Uno-style female header arrangement, allowing it to be used with these ubiquitous expansion shields as needed. It also has a WICED header arrangement for expansion. Along with the Bluetooth module, the board implements an ARM Cortex-M4 processor running at up to 96Mhz with 256 KB Flash, 176 KB SRAM, and a full MB ROM.
Even without adding a shield or other hardware, the board is quite capable on its own, featuring a 9-axis IMU, along with a thermistor for temperature sensing. Three buttons are available for recovery, reset, and user selectable, as well as LEDs for feedback. A wide range of jumpers are also available to enable or disable features and select supply voltage levels, and a CR2032 battery connector is available under the device.
CYBT-213043-MESH EZ-BT™ Module Mesh Evaluation Kit
A device capable of mesh networking is only so useful by itself, and so Cypress Semiconductor is also offering the EZ-BT WICED CYBT-213043-02 package. This kit includes not one, but four wireless modules, capable of Bluetooth basic and enhanced data rate, along with BLE for low power applications. This device features peripheral functions such as ADC and PWM, and a number of communication protocols in a form factor much smaller—roughly 3.7x1.8 inches—than its CYW20819 cousin, which measures in at approximately 4.8x2.9 inches.
The device can be programmed and powered via its micro USB port, and a jumper lets it also use a CR2302 coin cell battery. Three buttons for recover, reset, and user are provided with the other board, and an RGB LED is available for user feedback. These units also prominently feature a PIR motion sensor, making them ideal for smart home or security applications out of the box. Sensing and output capabilities can be expanded with GPIO pins, as well as communication protocols such as UART, SPI, and I2C.
The ModusToolbox software environment is available here to allow you to get started with these systems, and examples for using it are found on GitHub. Whether used alone, or as part of an integrated distributed network of sensors and IoT devices, these evaluation kits are a great way to get started with Bluetooth Mesh. You don’t even have to add external peripherals for many sensing applications! And, Cypress & Digi-Key are currently running the Make With Mesh contest. Enter here to win up to $2000US by building a Bluetooth 5 IoT project with one (or both, or multiple!) of their CYW20819 Bluetooth 5 Kits!
Jeremy S. Cook is a freelance tech journalist and engineering consultant with over 10 years of factory automation experience. An avid maker and experimenter, you can follow him on Twitter, or see his electromechanical exploits on the Jeremy S. Cook YouTube Channel!