MCU: attiny4313

Package: 20-pin PDIP

 1: PA2 dW   !Reset
 2: PD0 RXD0
 3: PD1 TXD0
 4: PA1 XTAL2
 5: PA0 XTAL1
 6: PD2 INT0 XCK0 CKOUT
 7: PD3 INT1
 8: PD4 T0
 9: PD5 T1 OC0B
10: Gnd
11: PD6 ICP
12: PB0 AIN0 PCINT0
13: PB1 AIN1 PCINT1
14: PB2 OC0A PCINT2
15: PB3 OC1A PCINT3
16: PB4 OC1B PCINT4
17: PB5 MOSI DI SDA PCINT5
18: PB6 MISO DO PCINT6
19: PB7 USCK SCK PCINT7
20: Vcc


Summary:
The high-performance Microchip picoPower 8-bit AVR RISC-based microcontroller
4 KB ISP flash memory with read-while-write capabilities,
256 Byte EEPROM,
256 Byte SRAM,
18 general purpose I/O lines,
32 general purpose working registers,
2  timer/counters (8-bitÁ 16-bit),
4-channel PWM,
1 comparators,
internal and external interrupts,
In-System Programmable via SPI Port,
programmable watchdog timer with internal oscillator,
The device operates between 1.8-5.5 volts.
