Birthday card code for ATtiny13A
A quick hack to create a musical birthday card. Plays "You Are My Sunshine" and blinks three LEDs.
A speaker is connected to pin 5 (PB0). The LEDs are connected to pins 2, 3, and 7 (PB2, PB3, PB4).
The wiring was created on the card using a Bare Paint Pen. This has enough resistance to not need any physical resistors. When prototyping, current limiting resistors should be used on the speaker and the LEDs.