Open Hive GSM and WiFi sensor nodes


You might want to read this document on our documentation space, all inline links will be working there.


This hybrid firmware supports two different hardware devices. Telemetry data is transmitted using HTTP. Both HX711 and ADS1231 load cell sensor chips are supported. The most recent firmware version is available at node-gprs-http.ino.

Open Hive Box with electronics

Open Hive Box GSM

Open Hive WiFi Node on workbench

Open Hive WiFi Node

Platform and supported peripherals



  • HX711 ADC weigh scale breakout board or

  • ADS1231 ADC weigh scale breakout board

  • DS18B20 digital thermometer

  • DHT33 (RHT04) digital humidity/temperature sensor

See also


Clone git repository

# Get hold of the source code repository including all dependencies
git clone

# Select this firmware
cd node-gprs-http

Configure firmware

Have a look at the source code node-gprs-http.ino and adapt feature flags and setting variables according to your environment:

When using a HX711 sensor:

#define isScaleHX711

When using an ADS1231 sensor:

#define isScaleADS1231

Enable AVR ATmega328 with GPRSbee GSM modem:

#define isGSM

#define APN ""

Enable ESP8266 with integrated WiFi:

#define isWifi

#define WLAN_SSID  "your-ssid"
#define WLAN_PW    "your-pw"

Configure load cell calibration settings:

// Use sketches "scale-adjust-hx711.ino" or "scale-adjust-ads1231.ino" for calibration

// The raw sensor value for "0 kg"
const long loadCellZeroOffset = 38623;

// The raw sensor value for a 1 kg weight load
const long loadCellKgDivider  = 11026;


Read about Firmwares for load cell adjustment to get these values.

Build instructions


The build system is based on PlatformIO.

Build firmware:


After successfully building it, you will find firmware images at

  • .pio/build/nodemcu/firmware.bin

  • .pio/build/nodemcu/firmware.elf

Upload to MCU

export MCU_PORT=/dev/ttyUSB0
make upload