Use a ATTiny85 (can be ATTiny45, ATTiny44) to make an Arduino just for US3.00 and name it as Tiny Arduino.
Tiny Arduino have only eight pins as shown in figure above, Pin4 is ground (Gnd), Pin8 is 5V (Vcc), Pin1 is Reset, Pin2 and Pin3 originally used to connecting the Crystal. In order to utilize all the IO, the internal oscillator (RC Oscillator) is used to replace the external clock which require a crystal. Therefore the Tiny Arduino is now come with five IO. Below shows the Arduino IO functions.
1. There are five IO, each IO can be Input or Output
2. Among the five IO, two of the IO can perform as PWM
3. Among the five IO, three of the IO can perform as Analog Input
I2C may require to extend the features of Tiny Arduino.
Tiny Arduino have only eight pins as shown in figure above, Pin4 is ground (Gnd), Pin8 is 5V (Vcc), Pin1 is Reset, Pin2 and Pin3 originally used to connecting the Crystal. In order to utilize all the IO, the internal oscillator (RC Oscillator) is used to replace the external clock which require a crystal. Therefore the Tiny Arduino is now come with five IO. Below shows the Arduino IO functions.
1. There are five IO, each IO can be Input or Output
2. Among the five IO, two of the IO can perform as PWM
3. Among the five IO, three of the IO can perform as Analog Input
I2C may require to extend the features of Tiny Arduino.
Step 1: Materials
1 x 5V power supply power supply
1 x Breadboard (Project board)
1 x ATtiny85 (This is our Tiny Arduino)
1 x Arduino Duemilanove (use to upload Sketch to ATTiny85)
1 x 10 uF capacitor (prevent Arduino duemilanove from automatically reset)
5 x LED
5 x Resistors
and some Wires
1 x Breadboard (Project board)
1 x ATtiny85 (This is our Tiny Arduino)
1 x Arduino Duemilanove (use to upload Sketch to ATTiny85)
1 x 10 uF capacitor (prevent Arduino duemilanove from automatically reset)
5 x LED
5 x Resistors
and some Wires
Step 2: Using an Arduino Duemilanove as an ISP
An ISP (in-system programmer) is required to upload sketch to the ATtiny85 since ATtiny85 does not come with serial interface. Here we use an Arduino Duemilanove as an ISP to upload sketch to the ATtiny85.
1. Connect the Arduino Duemilanove to the computer
2. Open the Arduino software , I’m using arduino-0023
3. Select File> Examples> ArduinoISP from menu as shown in figure
4. Select Tools> Board> Arduino Duemilanove or Nano w/ATmega328 or Arduino UNO from menu
5. Click on the Upload icon to begin upload Sketch to Arduino Duemilanove
Now the Arduino Duemilanove is becoming an ISP
For more detail: Simplest and Cheapest Arduino
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