MCU: ATmega32u4
 Package: 44 pin QFN

 1: PE6   INBT6 AIN0
 2: UVCC
 3: D-
 4: D+
 5: UGND
 6: UCAP
 7: VBUS
 8: PB0   SS    PCINT0
 9: PB1   ISCI  PCINT1
10: PB2   MOSI  PDI    PCINT2
11: PB3   MISO  PDO    PCINT3
12: PB7   !RTS  OC1C   OC0A   PCINT7
13: Reset
14: Vcc
15: Gnd
16: XTAL2
17: XTAL1
18: PD0   OC0B  SCL    INT0
19: PD1   SDA   INT1
20: PD2   INT2  RXD1
21: PD3   INT3  TXD1
22: PD5   XCK1  !CTS
23: Gnd
24: AVCC
25: PD4   ADC8  ICP1
26: PD6   T1    !OC4D  ADC9
27: PD7   T0    OC4D   ADC10
28: PB4   ADC11 PCINT4
29: PB5   OC1A  !OC4B  ADC12  PCINT5
30: PB6   OC1B  OC4B   ADC13  PCINT6
31: PC6   OC3A  !OC4A
32: PC7   ICP3  CLKO   OC4A
33: PE2   !HWB
34: Vcc
35: Gnd
36: PF7   ADC7  TDI
37: PF6   ADC6  TDO
38: PF5   ADC5  TMS
39: PF4   ADC4  TCK
40: PF1   ADC1
41: PF0   ADC0
42: AREF
43: Gnd
44: AVCC


Summary:
The high-performance, low-power Microchip 8-bit AVR RISC-based microcontroller
32 KB ISP flash memory with read-while-write capabilities, 
1 KB EEPROM, 
2,5 KB SRAM, 
26 general purpose I/O lines, 
32 general purpose working registers, 
JTAG interface for boundary-scan and on-chip debugging/programming, 
1 x 8-bit, 2 x 16-bit timer/counters with compare modes, 
8 PWM Channels
internal and external interrupts,
serial programmable USART, 
universal serial interface (USI) with start condition detector, 
12-channel 10-bit A/D converter, 
programmable watchdog timer with internal oscillator, 
SPI serial port, 
6 software selectable power saving modes,
on-chip Analog Comparator,
on-chip Temperature Sensor,
USB 2 Full-speed/Low Speed Device Module with Interrupt on Transfer Completion 

