Re-Programming the LilyTiny / LilyTwinkle

Contributors: bri_huang

Notes on Programming the ATtiny85

The ATtiny85 isn’t your everyday Arduino microcontroller. It packs a lot of punch for its small size.

The following Arduino commands should be supported:

• pinMode()
• digitalWrite()
• digitalRead()
• analogRead()
• analogWrite()
• shiftOut()
• pulseIn()
• millis()
• micros()
• delay()
• delayMicroseconds()
• SoftwareSerial

All 5 pins are general purpose digital I/Os (GPIO). This means that they can be used with both digitalWrite() and digitalRead().

Pins 0 and 1 support PWM output (analogWrite).

Pins 2, 3, & 4 are tied to A/D on the chip (analogRead).

While the ATtiny85 supports most of the things you need, there are some things it can’t do.

No Hardware Serial (UART)

The ATtiny85 does not have a built in hardware UART. If you try to compile any Arduino code with Serial.begin() or Serial.print() you’ll get an error. However, there is a work around for this -- using Software Serial. This tutorial shows an example of how to do this:

Tip: Looking for a quick reference guide for the ATtiny85? Click on the link below to download an image or PDF version from our resources!