Advantage of this sensor is fast and easy installing by the non qualified personal. The sensor is designed for large agriculture facility with many greenhouses where is needed to be controlled temperature and humidity, the atmospheric pressure is for control the motor of air inlet and outlet. With help of the sensor installed outside the greenhouse provide information about positive/negative pressure inside the greenhouse.

Finlay the software read accurate temp/humid value of the Si7021, and only atmospheric pressure of BMP180, the temperature sensor inside the BMP180 is used only by the sensor itself to provide accurate atmospheric pressure measurements.

The sensor can be used also for home automation, and drone applications where is needed correction of the UAV barometric sensor compared to the ground barometric sensor, also humidity measurement can help the pilot to calculate more accurate flying time.

See this project, there have solution for hardware based watch dog, can be easily transform to be usable for Arduino.

https://www.openhardware.io/view/636/Raspberry-PI-Hat

I am not familiar with this board. look good. But mine design have few leverages:

1. You can stack another shield on top.
2. Have hardware Watch Dog Timer in case of your R-PI freeze.

Is it possible to use the second ISP on my raspberypi 3 to connect NRF24L01+ and what will be the wiring diagram, also what have to change in mygsw library

I send command from remote control arduino read this command (i can see this in serial monitor) but this commands are not sending to gateway, my radio is working the sensor connect to gateway and controller. I use example Sketch given up in this page without changing anything.
Any idea whats wrong in my setup?

I need arduino code to send RAW sensor value, when sensor change his value to send this value to controller. The type of signals have to be V_LEVEL. Normally i will use this with analog sensors.

If somebody have this kind of code please share with us.

I read datasheet for DHT11 and 2 degree deviation is ok for them. Now i playing with DHT22 I try this #define SENSOR_TEMP_OFFSET -1.3, but nothing is changed the sensor still give me same value.

For some sensors is possible to make with offset, but some of the sensors changing their values 2 times in minute with + - 2 degree Celsius some times show more sometimes show less.

Is exist some way to calibrate DHT sensors? today i make a experiment assemble 5 nodes with 5 DHT11 sensors put all nodes on one table and leave them for some hours, and the result is the every sensor give different values about temperature and humidity + - MAX 5 degree Celsius around the real temperature in the room. Hardware used Arduino Nano X 5pc., HDT11 X 5pc., the power supply is 12V 2,2A enough to power all of the arduinos.

Both sketch not working giving me "error: 'saveState' was not declared in this scope

  saveState(CHILD_ID, state);"