PE6 (INT6/AIN0)
1
UVcc
2
D-
3
D+
4
U
G
n
d
5
UCap
6
VBus
7
PB0 (SS/PCINT0)
8
PB1 (PCINT1/SCK)
9
PB2 (PDI/MOSI/PCINT2)
10
PB3 (PDO/MISO/PCINT3)
11
PB7 (OC0A/OC1C/PCINT7/RTS)
12
RESET
13
VCC
14
G
ND
1
5
XTAL2
16
XTAL1
17
PD0 (INT0/SCL/OC0B)
18
PD1 (INT1/SDA)
19
PD2 (INT2/RXD1)
20
PD3 (INT3/TXD1)
21
PD5 (XCK1/CTS)
22
G
N
D
2
3
AVCC
24
PD4 (ICP1/ADC8)
25
PD6 (T1/OC4D/ADC9
26
PD7 (T0/OC4D/ADC10)
27
PB4 (PCINT4/ADC11)
28
PB5 (OC1A/OC4B/PCINT5/ADC12)
29
PB6 (OC1B/OC4B/PCINT6/ADC13)
30
PC6 (OC3A/OC4A)
31
PC7 (ICP3/CLK0/OC4A)
32
PE2 (HWB)
33
VCC
34
G
ND
3
5
PF7 (ADC7/TDI)
36
PF6 (ADC6/TDO)
37
PF5 (ADC5/TMS)
38
PF4 (ADC4/TCK)
39
PF1 (ADC1)
40
PF0 (ADC0)
41
AREF
42
G
N
D
4
3
AVCC
44
P
A
D
4
5
ATmega32U4
VBUS
1
D-
2
D+
3
ID
4
GND
5
N
C
6
N
C
7
N
C
8
N
C
9
N
C
1
0
N
C
11
USB Micro-B
1 uF
C2
5V
L1
10 uH
0.1 uF
C1
AVCC
5V
AVCC
0.1 uF
C3
VBUS
22
R2
22
R3
nRESET
D14
D16
D15
PD5
D2
Green
1.5k
R6
PD5
D8
D9
D10
D11
D3
D2
D0
D1
D4
D12
D6
D7
D5
D13
A0
A1
5V
D4
Yellow
2.21k
R10
D13
AREF
PE2
A2
A3
A4
A5
D17
D3
Red
2.21k
R7
D17
5V
Y1
16 MHz
10 pF
C4
10 pF
C5
SW1
SW3
Button B
SW4
Button C
1k
R8
3k
R12
3k
R13
1.5k
R9
SW2
Button A
D14
1k
R11
Buzzer
D1
Q1
100k
R14
5V
D6
20k
R4
VSW
BATLEV
10k
R5
A1
BZCTRL
(SDA)
(SCL)
(MOSI)
(MISO)
(SCK)
AVR3V3
(RXL/SS)
(TXL)
5V
c
lo
c
k
w
is
e
R1
D0
D1
D14
D17
D13
PD5
Vss
1
VDD
2
Vo
3
RS
4
R/W
5
E
6
DB0
7
DB1
8
DB2
9
DB3
10
DB4
11
DB5
12
DB6
13
DB7
14
LCD
3pi+ 32U4 Control Board
©
2020 Pololu Corporation
www.pololu.com
Schematic diagram
Microcontroller and user interface
Page 1 of 4
R
®
1
2
EMIT
D4
D5
D11
D12
A0
A2
A3
A4
BUMPL
BUMPR
DOWN1
DOWN2
DOWN3
DOWN4
DOWN5
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
3
1
2
3
D2
D3
5V
(SDA)
(SCL)
3V3
D0
D1
D6
A1
A5
PE2
1
2
4
3
5
6
7
D2
D3
(SDA)
(SCL)
1
2
4
3
5
6
7
5V
5V
MISO
1
VCC
2
SCK
3
MOSI
4
RST
5
GND
6
AVRISP
5V
nRESET
D14
D16
D15
Front expansion header
Mid expansion header
