So the solution is given (again) by Atmel with the ATtiny microcontrollers. Especially the ATtiny85 chip, which has 8 Kb flash memory, 6 input/output pins, low power supply at 1.8-5.5V, small 8-pin packaging and costs only 2-3$.
It is very easy to program the ATtiny85 using our own Arduino board based on the tutorial Arduino-based ATtiny programming published by MIT’s High-Low Tech research group.
In this instructable I will try to guide you step by step, through the whole procedure of constructing a small board – shield for the Arduino, so that the programming can be made easily and fast. This is what I named the ATtinyShield.
For more Arduino and ATtiny85 projects, check my blog: http://attiny85.blogspot.com
If anyone needs the PCB and/or the Shield premade check here:
(WITH NEW PCB CHECK PHOTO 4 below)
Step 1: What are we gonna do...
As pointed out by the MIT’s High-Low Tech tutorial, we have to connect the ATtiny85 (pins 1, 5, 6, 7) with 4 digital outputs of our Arduino (pins 10, 11, 12, 13), give 5V and Ground to pins 8 and 4 of the microcontroller and finally place a 10uF Electrolytic Capacitor between the Reset and Ground of the Arduino.
In my project I have added an indicator LED on pin 9 of the Arduino that shows that the programmer is running properly and a reset tact switch for the ATtiny85.
All this can be seen on both the schematics above.
So by creating a small shield with all these connections, it’s easy to plug it on our Arduino and worry only about the programming stuff.