In my last two posts I covered how I setup the Eclipse Ponte Bridge locally and how my Arduino Yun was reading a MQTT topic from the Ponte Bridge using HTTPClient. In this post I will cover how I used an ESP8266 with Arduino Uno to publish a MQTT message with RGB values.
In the earlier blog post, I introduced Ponte and set it up locally on my windows PC. In this post I will demonstrate how I used the HttpClient on the Arduino Yun to read the MQTT messages and light up the LED strip using the Infineon Shield. This code does not use any of the MQTT Client libraries to subscribe to a topic. It just uses the HttpClient available on Arduino Yun’s bridge library and keeps polling the HTTP bridge on the Ponte server for message availability.
This post guides your through setting up a swap file for extending the RAM on the Arduino Yun. In the last blog post, Arduino Yun OpenWrt upgrade, sftp and nodejs , I installed nodejs on my Arduino Yun. Then when I tried to install some more node packages using node package manager (npm) i ran in to “out of memory” issue.
FATAL ERROR: Evacuation Allocation failed – process out of memory
As i get to understand more about the capabilities of Yun, i did some basic house keeping work on the Yun. I expanded the disc space with a micro SD card. Upgraded the OpenWrt-Yun firmware and installed sftp and nodejs.
Thanks to Element14 I got my Arduino Yun today. The first thing i noticed was the power supply. No barrel jack. So it has to be powered through Micro USB. That’s fine when connected to a computer. But if you are powering it from wall wart or from batteries then it has to be the right specification because of the lack of built in regulator.
In Dec 2014, I was one of the finalist for the Holiday Lights Road Test challenge conducted by element14.com.I chose to build an Interactive WiFi Christmas Tree . I wrote several blog posts on element14.com to share my build process with the community. I am cross posting most of those blogs from element14.com to my blog. The following is the introductory post for what my project is about.