1. Displaying battery voltage, current, amp-hours, and other measurements
2. Sounding an alarm if the fridge gets too warm
3. Retracting the awning if the wind gets too strong
4. Turning off the water pump in the event of a pipe leak
Microcontrollers constantly monitor sensors and take necessary action. Many RVs already use a microcontroller in the form of the popular Tire Pressure Monitoring System---and some battery chargers also use a microcontroller.
However, with mine, I have complete control over all the parameters and actions. The sky's the limit---within budget, of course. I am notorious on this forum for my low-cost solutions, and my new microcontroller is no different. His name is HAL---kind of like that big computer in the movie 2001: A Space Odyssey---but mine's the size of a credit card, and he only costs about thirty dollars.
He's programmable using my laptop, which happens to be running the Ubuntu Linux operating system---though most any Apple or Windows laptop will also work. If you know how to program a computer, it's very similar. HAL seems to understand a variant of the C programming language. He has a micro-SD card slot, which means he can store gobs of data. He can communicate through a common USB cable when he's hooked to my laptop, but he'll do most of his "talking" using an $8 LCD display, which will arrive on Monday. In the mean time, already on his first day on the job, he's managed to send voltage measurements---accurate to better than a millivolt---to my laptop. Over the weekend, he'll learn how to tell time and write to an SD card.
HAL is of Arduino descent. Arduino was founded in Italy in 2005 on the concept that microcontrollers should be easy to program, be Open Source, and any extra hardware should be easy to attach. From those modest 8-bit beginnings, a group of students at MIT endowed it with 32 bit power, and the Maple Project was born. Then some enterprising folks at Olimex in Bulgaria took it a step further, adding the key features that made it suitable for RV use: industrial grade components, flexible power supply, real time clock, and SD card. The board has only been available for a few months now, so it will be quite fun to be on "the cutting edge" for a while.
Thanks go to Ned Pepper's Chaps for casually mentioning Arduino, and Roadwarrior for pointing out the new Olimexino.
Edited by Dugggg, 30 March 2012 - 07:57 PM.












