Category Archives: Sensors

Reverse engineer wireless devices protocols

According to Andreas Spiess, “Hacking of 433 MHz or other RF devices is a human right for makers because these devices usually use proprietary protocols…“. Take a look at his blog entry where he uses a Raspberry and RTL-SDR to reverse engineer protocols. Might be useful if you want to use cheap wireless weather sensors in your own project.

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Testing Various Low-Cost Hygrometers

In my search for humidity sensors I found a nice overview at kandrsmith where the following devices are tested:many_sensors_8bit

  • Bosch Sensortec BME280
  • Measurement Specialties HTU21D
  • Silicon Labs Si7021
  • Aosong DHT11, DHT22, AM2302, AM2320, AM2321

The test has main focus on humidity, but also discusses other aspects of the various devices.

 

MySensors

The guys over at MySensors are creating a big library for connecting typical sensors together. They have collected information for a lot of sensors, controllers and gateways  added source code and instructions for them. For example Display and Time, Temperature and battery powering. They also compare prices between AliExpress and Ebay for typical sensors in the store. A lot of info to be found. Take a look.

It’s a bit tricky to understand what they’re aiming at first time you visit, but here are some quotes from their pages:

“Learn how to create your own low cost wireless sensors and connect them to the world.”

“We’ve combined the Arduino platform with a small radio transceiver into a fun, flexible world of low cost wireless sensors.”

“All the nitty-gritty details about the sensor communication has been packaged into a convenient software library so you don’t have to worry about them.”