USD

Wireless XBee3 Micropython Platform and TE Connectivity’s Weather Shield

TE Connectivity’s Weather Shield combined with Digi International’s Micropython-capable XBee3 wireless modules makes a great wireless sensor prototyping platform.

Figure 1: Digi International Grove board, XBee3 module and TE Connectivity Weather Shield. (Image source: Digi International and TE Connectivity)

The Weather Shield is an Arduino form factor sensor evaluation board with five mounted TE environmental sensors. The sensors are a HTU21D Humidity/Temperature Sensor, MS5637 Pressure Sensor, MS8607 PHT (Pressure Humidity Temperature) Combination Sensor, TSYS01 Temperature Sensor, and TSD305-1C55 Contactless Temperature Sensor. Digi International’s XBee3 wireless modules feature embedded Micropython capability for intelligent standalone operation. Cellular and point-to-point or mesh 2.4 GHz radio versions of XBee3 wireless modules are available.

Project Description

The scope of the project was to develop and document example Micropython code and electrical interface between an XBee3 module and each of the five TE Connectivity sensors. For hardware I used an XB3-24Z8US-J 2.4 GHz wireless module mounted in an XBee SMT Grove Development Board and connected to a TE Connectivity Arduino Weather Shield over an I2C bus, as shown in Figure 2. The Weather Shield sensors communicate over an I2C bus routed through a CD74HC4502 mux/demux IC to allow switching of the I2C bus between the various sensors.

Figure 2: Electrical interface between Digi International Grove development board and TE Connectivity Weather Shield. (Diagram drawn using Digi-Key Scheme-it®)

HTU21D(F) Humidity/Temperature Sensor

TE Connectivity’s HTU21D(F) is a digital humidity sensor with temperature output in a DFN package with a small 3 x 3 x 0.9 mm footprint. The sensor provides calibrated, linearized signals in digital, I²C format and resolution of 8/12 bit up to 12/14 bit for RH/T (relative humidity/temperature). In the project, example code scans the I2C bus and prints active addresses, reads/prints the user register, and reads/prints relative humidity and temperature in a continuous loop. For project details and example code download, see Xbee3 Micropython and TE HTU21D Humidity Sensor.

MS5637 Pressure Sensor

TE Connectivity’s MS5637 is an ultra-compact micro altimeter in a QFN package with dimensions of 3 x 3 x 0.9 mm and an I²C interface. The sensor module includes a high-linearity pressure sensor and an ultra-low-power 24-bit ΔΣ-ADC (analog-to-digital-converter) with internal factory-calibrated coefficients. In the project, example code scans the I2C bus, prints active I2C addresses, resets the sensor, reads calibration data stored in onboard PROM, and reads/converts barometric pressure and temperature in a continuous loop. For project details and example code download, see Xbee3 Micropython and TE MS5637 Pressure Sensor.

MS8607 Pressure/Humidity/Temperature Sensor

TE Connectivity’s MS8607 sensor is a digital combination sensor providing three environmental physical measurements all-in-one: pressure, humidity and temperature (PHT). In the project, example code scans the I2C bus and prints active addresses, resets the sensor, reads calibration data stored in onboard PROM, and reads/converts barometric pressure, temperature and humidity in a continuous loop. For project details and example code download, see Xbee3 Micropython and TE MS8607 PHT Combination Sensor.

TSYS01 Temperature Sensor

TE Connectivity’s TSYS01 provides factory-calibrated temperature information and includes a temperature sensing chip and a 24-bit ΔΣ-ADC. The example code scans the I2C bus and prints active addresses, resets the sensor, reads calibration data stored in onboard PROM, and reads/converts temperature in a continuous loop. For project details and example code download, see Xbee3 Micropython and TE TSYS01 Temperature Sensor.

TSD305-1C55 Contactless Temperature Sensor

TE Connectivity's TSD305-1C55 contactless temperature sensor includes an infrared sensor (thermopile) and a sensor signal conditioner. The example code scans the I2C bus and prints active addresses, reads calibration data stored in onboard EEPROM and reads the ADC sensor and object data and converts to temperature in a continuous loop. For project details and example code download, see Xbee3 Micropython and TE TSD305 Contactless Temperature Sensor.

About this author

Image of Scott Raeker

Scott Raeker, Technical Marketing Manager at Digi-Key Electronics, has been with the company since 2006. He has over 35 years of experience in the electronics industry and holds an Electrical Engineering degree from the University of Minnesota. In his spare time, Scott enjoys the outdoors of Northwest Minnesota and working on his turn-of-the-century farmhouse.

More posts by Scott Raeker