Check out LoRa long-range IoT connectivity on STM32 eval boards

February 19, 2017 // By Graham Prophet
Two prototype boards available from STMicroelectronics cut the cost for developers to start evaluating the LoRaWAN and other Low-Power Wide Area Network (LPWAN) technologies including 6LoWPAN.

The boards are based on the smallest and lowest-power LoRaWAN modules that exist on the market today, with a footprint not larger than 13 x 12 mm and power consumption in the range of 1.2 µA in standby mode.

The B-L072Z-LRWAN1 STM32 LoRa Discovery kit ($46.50) builds on the all-in-one open module from Murata that integrates a STM32L072CZ microcontroller and Semtech SX1276 transceivers. The module features a LoRa modem that provides ultra-long-range spread-spectrum communication and high interference immunity whilst minimizing current consumption.

Since the module is open, developers have access to the STM32L072 MCU and its peripherals such as ADC, 16-bit timer, LP-UART, I ²C, SPI and USB 2.0 FS (supporting BCD and LPM). They can design their applications using STM32L0 HAL and LL embedded software libraries, and can further extend the board's functionality choosing from expansion boards within the STM32 Nucleo ecosystem or the large range of Arduino expansion boards.

The B-L072Z-LRWAN1 kit includes an on-board debugger, a 64-pin STM32 Nucleo morpho connector, an Arduino-compatible connector, and a battery socket. It also comes with access to a free development ecosystem that includes the MDK-ARM Integrated Development Environment (IDE), STM32CubeMX configurator and software tools, and ST's LoRaWAN protocol stack ( I-CUBE-LRWAN).

The I-NUCLEO-LRWAN1 ($25.00) is an expansion board for STM32 Nucleo or Arduino boards that can be plugged in to start work developing a full LoRa-based and/or FSK/OOK (Frequency-Shift Keying/On-Off Keying) connectivity applications. The board features a LoRaWAN module from USI together with an STM32L052T8 MCU and Semtech SX1272 transceivers.

The USI module comes pre-loaded with an AT command stack that helps streamline development and saves programming. The I-CUBE-LRWAN stack is available free of charge. To aid development of IoT applications, the I-NUCLEO-LRWAN1 board is also equipped with ST's LIS2DS12 3-axis accelerometer, LPS22HB MEMS pressure sensor, and HTS221 humidity-and-temperature sensor.

Both boards are LoRaWAN-certified and fully compliant with wireless regulations in the US, EU, Russia, India, and other