This is my first post on home automation. As a 'Hello World' project, switching on/off a bulb is a common use case. This post is not an exception. But to spice it up, we'll use MQTT (MQ Telemetry Transport) - a machine-to-machine (M2M)/Internet of Things (IOT) connectivity protocol and an android app (IoT MQTT Dashboard). Bulb is merely a symbolic representation of an electrical device. We can practically control any device (Internet of Things) over internet.
Configure STA_IF interface of ESP8266 (MycroPython firmware) to connect with WIFI network automatically on boot
ESP8266 can act as both Station / WIFI client (STA_IF interface) and Access Point (AP_IF interface). AP_IF interface is active by default in MycroPython firmware on ESP826 . In the earlier post, we connected to the access point (AP mode) of ESP8266 and used WebREPL to remotely control switch on/off and brightness of an LED. Now, we'll configure the ESP8266 (as WIFI client) so that it connects to the WIFI router automatically after booting.
So far, we have flashed MicroPython firmware onto an ESP8266 and setup WebREPL to run programs over WIFI on the chip. Now it's time for a hands-on excercise. We'll remotely switch on/off and control brightness of an LED using MicroPython WebREPL.
WebREPL daemon auto-start is disabled by default in MycroPython on ESP8266 for security reason. Here, we'll enable the same, connect to the REPL over WIFI using locally installed WebREPL client and run a "Hello World" program remotely on the chip.
By default, ESP8226 module comes with AT Firmware. In this post, we'll see how to flash MicroPython firmware onto an ESP8266 ESP-12E chip using esptool.
To uninstall OpenCV (Open Source Computer Vision) from Raspberry Pi (Raspbian Jessie), follow the steps mentioned below in this article.
Raspberry Pi is a low cost, credit-card sized and fastest selling personal computer. In this article, we'll install and configure Oracle Java ME Embedded on a Raspberry Pi.
Apache Hadoop Development Tools (HDT) is still in development phase. So, no official distribution of Hadoop 2.2.0 Eclipse Plugin is available now. But we can build the same using winghc/hadoop2x-eclipse-plugin. In this post, we'll build, install and configure the plugin with the Eclipse or any Eclipse based IDE (say, Spring Tool Suite) to ease the development activities using Hadoop framework.
Shell$ExitCodeException - Caused by: java.lang.NoClassDefFoundError: org/apache/hadoop/service/CompositeService
If you are getting "Exception from container-launch:org.apache.hadoop.util.Shell$ExitCodeException" in FAILED application's Diagnostics (or Command prompt) and "java.lang.NoClassDefFoundError: org/apache/hadoop/service/CompositeService" in 'stderr' containerlogs while running any Hadoop example on Windows, then add all the required Hadoop jars to the property 'yarn.application.classpath' in yarn-site.xml configuration file.
In this post, we'll use HDFS command 'bin\hdfs dfs' with different options like mkdir, copyFromLocal, cat, ls and finally run the wordcount MapReduce job provided in %HADOOP_HOME%\share\hadoop\mapreduce\hadoop-mapreduce-examples-2.2.0.jar. On successful execution of the job in the Single Node (pseudo-distributed mode) cluster, an output (contains counts of the occurrences of each word) will be generated.