Reverse engineering a BLE clock

Perfect Time

© Photo by ANIRUDH on Unsplash

© Photo by ANIRUDH on Unsplash

Article from Issue 272/2023
Author(s):

What do you do when all your Bluetooth clocks show slightly different times? With some reverse engineering, you can write a Python program to synchronize your clocks.

A while ago, I bought a ThermoPro TP358, a Bluetooth Low Energy (BLE) digital thermometer with a display. The ThermoPro shows the temperature, humidity, and air comfort indicator, as well as the time and day of the week. Its big display is nice for immediate feedback, but the device also lets you read its values and view graphs in the ThermoPro Sensor app, available on Android and iOS (Figure 1). Moreover, every time you connect to the device with the app, it synchronizes the time.

Figure 1: The ThermoPro Sensor app synchronizes the time of the digital thermometer upon connection.

While that is a nice feature, I have a couple of other types of Bluetooth sensors with a clock, and I didn't want to use multiple apps to view the sensor measurements and synchronize the clocks. For the sensor measurements, a solution already exists: Software such as Home Assistant [1] supported my devices out-of-the-box, letting me view their measurements in Home Assistant's dashboard. However, I couldn't find any solution that let me synchronize the time across all of my Bluetooth clocks without using the individual apps.

[...]

Use Express-Checkout link below to read the full article (PDF).

Buy this article as PDF

Express-Checkout as PDF
Price $2.95
(incl. VAT)

Buy Linux Magazine

SINGLE ISSUES
 
SUBSCRIPTIONS
 
TABLET & SMARTPHONE APPS
Get it on Google Play

US / Canada

Get it on Google Play

UK / Australia

Related content

comments powered by Disqus
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters

Support Our Work

Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

Learn More

News