Showing posts from December, 2017

IoT temperature sensor with ESP8266 using LWM2M (Eclipse Wakaama)

The sensor uses an ESP8266 board with the protocol Lightweight M2M to communicate the temperature read by DS18B20 to the gateway. The sources of the project are available on GitHub:

ESP8266The ESP8266 is a low-cost Wi-Fi microchip with full TCP/IP stack and microcontroller capability produced by Espressif Systems. The avalability of same SDK allows the chip to be programmed, removing the need for a separate microcontroller. To program the microchip i use the SDK Arduino core for ESP8266 WiFi chip and PlatformIO, that is an open source ecosystem for IoT development. LwM2M Lightweight M2M is a protocol from the Open Mobile Alliance for M2M or IoT device management and communication. It uses CoAP, a light and compact protocol with an efficient resource data model, for the application layer communication between LWM2M Servers and LWM2M Clients. Each service on a constrained device/sensor/actor is modelled as an LWM2M o…

Build an Android app to control a Q7 Camera P2P WIFI

This tutorial will teach you how to build an Android app to control a Q7 Camera P2P WIFI using the Android Studio development environment.

Start a new project
I create a new project with application name "Q7Camera". During the wizard i add a basic activity.

Import native libraries and sources To control the camera you need the libraries at this link: Copy the previous library in the path "app/src/main/jniLibs/armeabi" of your project. The packages to import are x1.Studio.Core at and com.microembed.sccodec at

Edit the manifest To use the native libraries you need to add the following permissions to the manifest:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="a…

Connect wan automatically at boot and after a disconnection on OpenWrt

OpenWrt is an open source project for embedded operating system based on Linux, primarily used on embedded devices to route network traffic. I install OpenWrt on my Netgear DGN3500, an ADSL2+ gateway with wireless acccess point integrated. Finally the wifi signal is strong but the internet connection does not go up at boot or after a disconnection.

Found solutions I find the following solutions: to schedule the reboot and the reconnections by cron (, to write a script to reconnect after a disconnection ( or to insert the command "ifup wan" in the file "/etc/init.d/network".

Recomended solutionTo take all the advantages of the previous solutions i write the script "wanup" to connect the wan and i call its at boot and after the disconnection. To call the script "wanup" at boot you can insert t…