I have a very very basic knowledge of electronics and would like to try learn more, i want to start my own project.
What I'd like is two temp sensors and when they hit 25 degrees to trigger 4 fans which are Pwm controlled. As the temp increases the fan speed increases.
Board needs to run on 12v
Need two sensors to monitor temperature
4x Pwm Fan outputs, min of 1amp each
Get some nice little boards made up
Anyone willing to offer advice on where and how to start this project?
Anyone willing to offer advice on where and how to start this project?
The project sounds, from a programming point of view, almost trivial. The requirements are incomplete.
As the temp increases the fan speed increases.
By how much? If the temperature is 25, should the fan PWM value be zero? Does a 1 degree temperature rise cause the PWM value to increase by 1? By 10? By 100?
I'm sure it is trivial if you know what your doing and probably someone could knock something up in a few hours.
I'm thinking 25 degrees 25% fan power, 27 Degree 50% fan power, 29 degrees 75% power and 31% full power
Fans stay on till temp goes back down to 25 degrees.
I need help with every single thing i pretty much know nothing
You should probably start by buying a PWM controllable fan, an Arduino, and a temperature sensor and work on having the temperature sensor control the fan. If you run into any problems, you can ask, but we are mostly unwilling to do the project for you, especially if you aren't going to put any effort into it. We will help when you get stuck.
Well start by what I said, get an appropriate PWM fan, an arduino and a temperature sensor. And it sounds like you have the temperature sensor picked out.
Have you chosen out fans?
If not check http://www.digikey.com or any of the other electronics distributors. Figure out what kind of size you need, and how much airflow. Make sure it has a PWM input, that way you don't have to include complicated extra hardware. As for air flow, what are you trying to cool?
While we can give you pointers, I'm not sure any of us will want to bother helping you program ATTinys, since they are not really Arduinos and have significant changes to be made to support the arduino format. I would go ask for help on AVRfreaks instead. These are the arduino forums after all. It would be far simpler for you to use an arduino at the beginning and then see about translating it to the smaller device. Or built it for the smaller device to begin with, but ask around on AVR Freaks. Most of us are going to tell you to use libraries you won't have access to on the ATTIny.