All of the ATtiny’s are basically the same apart from the number of actual IO pins and a few specific features.
ATtiny24 / ATtiny44 / ATtiny84
14pin
Internal osc +-10% without user calibration (ATtiny841 is drop in replacement with better accuracy)
ATtiny85
8 pin
ATtiny441 / ATtiny841
14 pin
Internal osc +-2% without user calibration
Default pin numbering to use: Counterclockwise
// ATMEL ATTINY84 ARDUINO PIN NUMBERS - "COUNTERCLOCKWISE" PIN MAPPING OPTION
// +-\/-+
// [VCC] VCC 1| |14 GND [GND]
// _0_ PB0 2| |13 AREF _10_
// _1_ PB1 3| |12 PA1 _9_
// [RST] PB3 4| |11 PA2 _8_
// _2_ PB2 5| |10 PA3 _7_
// _3_ PA7 6| |9 PA4 _6_ [SCK]
// [MOSI] _4_ PA6 7| |8 PA5 _5_ [MISO]
// +----+
// [Programmer pins in brackets]So, if you have a LED connected to pin 11, you’d declare it as this:
#define IO_LED 8 //PA2UART pins for serial programming
(UART0 default pins):
4 – PB3, RESET
11 – PA2, RXD0
12 – PA1, TXD0
Analog pins
Example:
PB0 is accessed using analogRead(A11)
ATtiny861
20 pin
USEFUL?
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