Replacing the DHT22 with a Bosch BME280

I compared the humidity readings from two DHT22 and was alarmed by the difference between them.

Although they are cheap, the Bosch BME280 doesn't have to cost that much more, and provides pressure measurement in addition to humidity and temperature.

Although many of the BME280s available cost around £20, I splashed out £7.61 and bagged a bargain on Amazon.

RaspberryPi + DS18B20 Temperature Sensor

The DS18B20 is a low cost, simple to use, 1-wire temperature sensor which is ideally suited for use with the Raspberry Pi.

Up to 10 of these sensors can be wired in parallel to a single Raspberry Pi GPIO pin, each giving a reasonably accurate indication of temperature.

The current Raspbian image includes support for these devices, so its quite easy to get them up and running.

Pi-Mote + RaspberryPi: checking the range

The RaspberryPi fitted with a Pi-Mote controller is a neat 433MHz remote control solution for switching mains powered equipment.

But to be of any use, the operation range must be sufficient to satisfy the requirements of your application.

So I set about doing a few range tests and have detailed my method and results here.

The Pi-Mote 433MHz control unit for the RaspberryPi

This controller allows a user to remotely control power sockets via a simple program.

Having just received my kit from Energenie, this post is basically an introduction to using the system, driven by a Gambas program.

I've also included information on the serial data format, which was captured using the method described in an earlier post.