OLIMEX© 2018
STM32-H407 user's manual
Page 26 of 30
ETH_RMII_REF_CLK
ETH_RMII_MDIO
ETH_RMII_MDINT
ETH_RMII_CRS_DV
ETH_RMII_TX_EN
ETH_RMII_MDC
ETH_RMII_RXD0
ETH_RMII_RXD1
ETH_RMII_TXD0
ETH_RMII_TXD1
6-16VDC
FSMC_A0
FSMC_A1
FSMC_A2
FSMC_A3
FSMC_A4
FSMC_A5
FSMC_A6
FSMC_A7
FSMC_A8
FSMC_A9
FSMC_D12
FSMC_D11
FSMC_D10
FSMC_D9
FSMC_D8
FSMC_D7
FSMC_D6
FSMC_D5
FSMC_D4
FSMC_A22
FSMC_A21
FSMC_A20
FSMC_A19
FSMC_A23
FSMC_D1
FSMC_D0
FSMC_A18
FSMC_A17
FSMC_A16
FSMC_D15
FSMC_D14
FSMC_D13
FSMC_NE1
FSMC_NWAIT
FSMC_NWE
FSMC_NOE
FSMC_CLK
FSMC_D3
FSMC_D2
FSMC_NBL0
FSMC_NBL1
FSMC_NIORD
FSMC_NREG
FSMC_NIOWR
FSMC_CD
FSMC_INTR
FSMC_A10
FSMC_A11
FSMC_A12
FSMC_A13
FSMC_A14
FSMC_A15
FSMC_INT2
FSMC_NE2/FSMC_NCE3
FSMC_NCE4_1/FSMC_NCE3
FSMC_NCE4_2
MP1482DS
Close
WF2S
Close
Close
HN1x3(B0_1:Open;B0_0:Close)
HN1x3(B1_1:Open;B1_0:Close)
47pF(NA)
47pF(NA)
100uF/35V/LOWESR/105C/6.3x11mm_RM2.5
10
0n
F
100nF
10
0n
F
22uF/6.3V
47pF(NA)
47pF(NA)
100nF
100uF/35V/LOWESR/105C/6.3x11mm_RM2.5
10
0n
F
2.2uF/6.3V
10
uF
/6
.3
V
10
uF
/6
.3
V
10
0n
F
10
uF
/6
.3
V
10
uF
/6
.3
V
10
0n
F
10
0n
F
10
0n
F
10
0n
F
10
0n
F
10
0n
F
10
0n
F
10
0n
F
2.2uF/6.3V
10uF/6.3V
100nF
100nF
27pF
27pF
15pF
15pF
100nF
100nF
100nF
22pF
22uF/6.3V
22uF/6.3V
22uF/6.3V
100nF
100uF/16V/mini
220uF/16V/mini
22uF/6.3V
47
0u
F
/2
5V
/L
O
W
E
S
R
/1
05
C
10
0n
F
10nF
3.3nF
22uF/6.3V
22uF/6.3V
NA(PN1X6)
NA(PN1X6)
NA(PN1X8)
NA(PN1X8)
NA(ESDA6V1L)
NA(ESDA6V1L)
BAT54C
SMBJ16A
BH20R
C
L
47
0n
H
/0
80
5/
1.
7
6R
/2
50
m
A
FB0805/600R/200mA(201209-601)
FB0805/600R/200mA(201209-601)
F
B
08
05
/6
00
R
/2
00
m
A
(2
01
20
9-
60
1)
10uH/2.3A/YS75/7x8
2.2uH/3A/YS75/7x8
LED/GREEN/0603
VIN
VIN
NA(BH20S)
NA(BH20S)
NA(BH20S)
NA(BH20S)
YDJ-1136
LE
D
/R
E
D
/0
60
3
HN2x3(1-2:Close)
Q12.000MHz/HC-49SM(SMD)/20pF
32768Hz/6pF
0R(board_mounted)
15R
NA
15R
NA
NA
1M
0R(board_mounted)
15R
15R
0R
(b
oa
rd
_m
ou
nt
ed
)
N
A
(1
0k
)
N
A
(1
0k
)
NA
4.7k
15R
4.7k
NA
10k/1%
150R
1k
NA
NA
NA
NA
NA
NA
NA
NA
4.7k
4.7k
47k/1%
4.99k/1%
1k
1k
1k
47k/1%
1.1k/1%
47k
2.2k
1.1k/1%
4.99k/1%
T
11
07
A
-6
_3
.8
_2
.5
33
k
33
k
33
k
33
k
NA(10k)
NA(10k)
NA(10k)
NA(10k)
10k
10k
10k
33k
33k
33k
33k
MICRO
NA(USBLC6-2P6)
MIC2026-1YM
NA(USBLC6-2P6)
NA(HN1X3)
N
A
(2
xP
N
1x
6_
2x
P
N
1x
8)
STM32F407ZGT6
NA
BH10R
USB_A_VERTICAL
USB-OTG
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
+5V
3.3V
3.3V
3.3V
+5V
+5V
3.3V
3.3V_A
3.3V
+5V
+5V
3.3V
+5V
3.3V
3.3V
3.3V
3.3V
+5V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
3.3V
T1107A-6_3.8_2.5
+5V_EXT
+5V_HOST_PWR
+5V_HOST_PWR
+5V_JTAG
+5V_JTAG
+5V_OTG_PWR
+5V_OTG_PWR
+5V_OTG_PWR
AGND
AREF
AREF
BOOT0
LED
LED
PA0/WKUP
PA0/WKUP
PA1/D8
PA1/D8
PA2/USART2_TX
PA2/USART2_TX
PA3/USART2_RX
PA3/USART2_RX
PA4/D10/SPI1_NSS
PA4/D10/SPI1_NSS
PA5/D13/SPI1_SCK
PA5/D13/SPI1_SCK
PA6/D12/SPI1_MISO
PA6/D12/SPI1_MISO
PA7/D11/SPI1_MOSI
PA7/D11/SPI1_MOSI
PA8/USB_HS_VBUSON
PA8/USB_HS_VBUSON
PA8/USB_HS_VBUSON
PA9/OTG_FS_VBUS
PA9/OTG_FS_VBUS
PA10/USB_FS_VBUSON
PA10/USB_FS_VBUSON
PA10/USB_FS_VBUSON
PA11/OTG_FS_DM
PA11/OTG_FS_DM
PA12/OTG_FS_DP
PA12/OTG_FS_DP
PA13/TMS
PA13/TMS
PA14/TCK
PA14/TCK
PA15/TDI
PA15/TDI
PB0/A2
PB0/A2
PB1/A3
PB1/A3
PB2
PB3/TDO
PB3/TDO
PB4/TRST
PB4/TRST
PB4/TRST
PB5/USB_HS_FAULT
PB5/USB_HS_FAULT
PB5/USB_HS_FAULT
PB6/USB_FS_FAULT
PB6/USB_FS_FAULT
PB6/USB_FS_FAULT
PB8/I2C1_SCL
PB8/I2C1_SCL
PB9/I2C1_SDA
PB9/I2C1_SDA
PB10/SPI2_SCK/UART3_TX
PB10/SPI2_SCK/UART3_TX
PB10/SPI2_SCK/UART3_TX
PB12/OTG_HS_ID
PB12/OTG_HS_ID
PB12/OTG_HS_ID
PB12/OTG_HS_ID
PB13/OTG_HS_VBUS
PB13/OTG_HS_VBUS
PB14/OTG_HS_DM
PB14/OTG_HS_DM
PB15/OTG_HS_DP
PB15/OTG_HS_DP
PC0/A0
PC0/A0
PC1/A1
PC1/A1
PC2/SPI2_MISO
PC2/SPI2_MISO
PC3/SPI2_MOSI
PC3/SPI2_MOSI
PC4/A4
PC4/A4
PC5/A5
PC5/A5
PC6/USART6_TX
PC6/USART6_TX
PC7/USART6_RX
PC7/USART6_RX
PC8/SD_D0
PC8/SD_D0
PC9/SD_D1
PC9/SD_D1
PC10/SD_D2
PC10/SD_D2
PC11/SD_D3
PC11/SD_D3
PC12/SD_CLK
PC12/SD_CLK
PD0
PD0
PD1
PD1
PD2/SD_CMD
PD2/SD_CMD
PD2/SD_CMD
PD3
PD3
PD4
PD4
PD5
PD5
PD6
PD6
PD7
PD7
PD8
PD8
PD9
PD9
PD10
PD10
PD11
PD11
PD12
PD12
PD13
PD13
PD14
PD14
PD15
PD15
PE0
PE0
PE1
PE1
PE2
PE2
PE3
PE3
PE4
PE4
PE5
PE5
PE6
PE6
PE7
PE7
PE8
PE8
PE9
PE9
PE10
PE10
PE11
PE11
PE12
PE12
PE13
PE13
PE14
PE14
PE15
PE15
PF0
PF0
PF1
PF1
PF2
PF2
PF3
PF3
PF4
PF4
PF5
PF5
PF6
PF6
PF7
PF7
PF9
PF9
PF10
PF10
PF11
PF11
PF12
PF12
PF13
PF13
PF14
PF14
PF15
PF15
PG0
PG0
PG1
PG1
PG2
PG2
PG3
PG3
PG4
PG4
PG5
PG5
PG6
PG6
PG7/D2
PG7/D2
PG7/D2
PG8/D3
PG8/D3
PG8/D3
PG9
PG9
PG10
PG10
PG11
PG11
PG12/D4
PG12/D4
PG12/D4
PG13/D5
PG13/D5
PG13/D5
PG14/D6
PG14/D6
PG14/D6
PG15/D7
PG15/D7
PG15/D7
RB7/UEXT_CS
RB7/UEXT_CS
RB11/D9/UART3_RX
RB11/D9/UART3_RX
RB11/D9/UART3_RX
RF8
RF8
RST
RST
RST
RST
USB
USB
USB_HOST_D-
USB_HOST_D-
US
US
USB_OTG_D-
USB_OTG_D-
VBAT
1
2
3.3V_E
1
2
3V_BAT
1
2
AGND_E
1
2
AREF_EN
1
2
3
B0_1/B0_0
1
2
3
B1_1/B1_0
C1
C2
C3
C
4
C5
C
6
C7
C8
C9
C10
C11
C
12
C13
C
14
C
15
C
16
C
17
C
18
C
19
C
20
C
21
C
22
C
23
C
24
C
25
C
26
C27
C28
C29
C30
C31
C32
C33
C34
C35
C36
C37
C38
C39
C40
C41
C42
C43
C44
C45
C
46
C
47
C48
C49
C50
C51
1
2
3
4
5
6
CON1
1
2
3
4
5
6
CON2
1
2
3
4
5
6
7
8
CON3
1
2
3
4
5
6
7
8
CON4
D1
D2
D3
D4
GND_PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
JTAG
L1
L2
L3
L4
L5
L6
LED
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PD
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PE
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PF
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PG
PWR_JACK
P
W
R
_L
E
D
1
2
3
4
5
6
PWR_SEL
Q1
Q2
1
2
R-T
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R
11
R
12
R
13
R14
R15
R16
R17
R18
R19
R20
R21
R22
R23
R24
R25
R26
R27
R28
R29
R30
R31
R32
R33
R34
R35
R36
R37
R38
R39
R40
R41
R42
RESET
R
M
1G
1
R
M
1G
2
R
M
1G
3
R
M
1G
4
RM2G1
RM2G2
RM2G3
RM2G4
RM3G1
RM3G2
RM3G3
RM4G1
RM4G2
RM4G3
RM4G4
CD/DAT3/CS
2
CLK/SCLK
5
CMD/DI
3
DAT0/DO
7
DAT1/RES
8
DAT2/RES
1
VDD
4
VSS
6
SD/MMC
1
2
3
4
5
6
U1
ENA
1
ENB
4
FLAG_A
2
FLAG_B
3
GND
6
IN
7
OUT_A
8
OUT_B
5
U2
1
2
3
4
5
6
U3
1
2
3
U3BOOT
3V3
5V
A0
A1
A2
A3
A4
A5
AREF
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
GND
GND
GND
RST
VIN
U4
BOOT0/VPP
138
NRST
25
PA0/WKUP/USART2_CTS/USART4_TX/ETH_MII_CRS/TIM2_CH1_ETR/TIM5_CH1/TIM8_ETR/ADC123_CH0
34
PA1/USART2_RTS/USART4_RX/ETH_RMII_REF_CLK/ETH_MII_RX_CLK/TIM5_CH2/TIM2_CH2/ADC123_IN1
35
PA2/USART2_TX/TIM5_CH3/TIM9_CH1/TIM2_CH3/ETH_MDIO/ADC123_IN2
36
PA3/USART2_RX/TIM5_CH4/TIM9_CH2/TIM2_CH4/OTG_HS_ULPI_D0/ETH_MII_COL/ADC123_IN3
37
PA4/SPI1_NSS/SPI3_NSS/USART2_CK/DCMI_HSYNC/OTG_HS_SOF/I2S3_WS/ADC12_IN4/DAC1_OUT
40
PA5/SPI1_SCK/OTG_HS_ULPI_CK/TIM2_CH1_ETR/TIM8_CHIN/ADC12_IN5/DAC2_OUT
41
PA6/SPI1_MISO/TIM8_BKIN/TIM13_CH1/DCMI_PIXCLK/TIM3_CH1/TIM1_BKIN/ADC12_IN6
42
PA7/SPI1_MOSI/TIM8_CH1N/TIM14_CH1/TIM3_CH2/ETH_MII_RX_DV/TIM1_CH1N/RMII_CRS_DV/ADC12_IN7
43
PA8/MCO1/USART1_CK/TIM1_CH1/I2C3_SCL/OTG_FS_SOF
100
PA9/USART1_TX/TIM1_CH2/I2C3_SMBA/DCMI_D0/OTG_FS_VBUS
101
PA10/USART1_RX/TIM1_CH3/OTG_FS_ID/DCMI_D1
102
PA11/USART1_CTS/CAN1_RX/TIM1_CH4/OTG_FS_DM
103
PA12/USART1_RTS/CAN1_TX/TIM1_ETR/OTG_FS_DP
104
PA13/JTMS-SWDIO
105
PA14/JTCK-SWCLK
109
PA15/JTDI/SPI3_NSS/I2S3_WS/TIM2_CH1_ETR/SPI1_NSS
110
PB0/TIM3_CH3/TIM8_CH2N/OTG_HS_ULPI_D1/ETH_MII_RXD2/TIM1_CH2N/ADC12_IN8
46
PB1/TIM3_CH4/TIM8_CH3N/OTG_HS_ULPI_D2/ETH_MII_RXD3/OTG_HS_INTN/TIM1_CH3N/ADC12_IN9
47
PB2/BOOT1
48
PB3/JTDO/TRACESWO/SPI3_SCK/I2S3_CK/TIM2_CH2/SPI1_SCK
133
PB4/NJTRST/SPI3_MISO/TIM3_CH1/SPI1_MISO
134
PB5/I2C1_SMBA/CAN2_RX/OTG_HS_ULPI_D7/ETH_PPS_OUT/TIM3_CH2/SPI1_MOSI/SPI3_MOSI/DCMI_D10/I2S3_SD
135
PB6/I2C1_SCL/TIM4_CH1/CAN2_TX/OTG_FS_INTN/DCMI_D5/USART1_TX
136
PB7/I2C1_SDA/FSMC_NL/DCMI_VSYNC/USART1_RX/TIM4_CH2
137
PB8/TIM4_CH3/SDIO_D4/TIM10_CH1/DCMI_D6/OTG_FS_SCL/ETH_MII_TXD3/I2C1_SCL/CAN1_RX
139
PB9/SPI2_NSS/I2S2_WS/TIM4_CH4/TIM11_CH1/OTG_FS_SDA/SDIO_D5/DCMI_D7/I2C1_SDA/CAN1_TX
140
PB10/SPI2_SCK/I2S2_CK/I2C2_SCL/USART3_TX/OTG_HS_ULPI_D3/ETH_MII_RX_ER/OTG_HS_SCL/TIM2_CH3
69
PB11/I2C2_SDA/USART3_RX/OTG_HS_ULPI_D4/ETH_RMII_TX_EN/ETH_MII_TX_EN/OTG_HS_SDA/TIM2_CH4
70
PB12/SPI2_NSS/I2S2_WS/I2C2_SMBA/USART3_CK/TIM1_BKIN/CAN2_RX/OTG_HS_ULPI_D5/ETH_RMII_TXD0/ETH_MII_TXD0/OTG_HS_ID
73
PB13/SPI2_SCK/I2S2_CK/USART3_CTS/TIM1_CH1N/CAN2_TX/OTG_HS_ULPI_D6/ETH_RMII_TXD1/ETH_MII_TXD1/OTG_HS_VBUS
74
PB14/SPI2_MISO/TIM1_CH2N/TIM12_CH1/OTG_HS_DM/USART3_RTS/TIM8_CH2N
75
PB15/SPI2_MOSI/I2S2_SD/TIM1_CH3N/TIM8_CH3N/TIM12_CH2/OTG_HS_DP
76
PC0/OTG_HS_ULPI_STP/ADC123_IN10
26
PC1/ETH_MDC/ADC123_IN11
27
PC2/SPI2_MISO/OTG_HS_ULPI_DIR/ETH_MII_TXD2/ADC123_IN12
28
PC3/SPI2_MOSI/I2S2_SD/OTG_HS_ULPI_NXT/ETH_MII_TX_CLK/ADC123_IN13
29
PC4/ETH_RMII_RX_D0/ETH_MII_RX_D0/ADC12_IN14
44
PC5/ETH_RMII_RX_D1/ETH_MII_RX_D1/ADC12_IN15
45
PC6/SPI2_MCK/TIM8_CH1/SDIO_D6/USART6_TX/DCMI_D0/TIM3_CH1
96
PC7/SPI3_MCK/TIM8_CH2/SDIO_D7/USART6_RX/DCMI_D1/TIM3_CH2
97
PC8/TIM8_CH3/SDIO_D0/TIM3_CH3/USART6_CK/DCMI_D2
98
PC9/I2S2_CKIN/I2S3_CKIN/MCO2/TIM8_CH4/SDIO_D1/I2C3_SDA/DCMI_D3/TIM3_CH4
99
PC10/SPI3_SCK/I2S3_CK/UART4_TX/SDIO_D2/DCMI_D8/USART3_TX
111
PC11/UART4_RX/SPI3_MISO/SDIO_D3/DCMI_D4/USART3_RX
112
PC12/UART5_TX/SDIO_CK/DCMI_D9/SPI3_MOSI/I2S3_SD/USART3_CK
113
PC13/RTC_AF1
7
PC14/OSC32_IN
8
PC15/OSC32_OUT
9
PD0/FSMC_D2/CAN1_RX
114
PD1/FSMC_D3/CAN1_TX
115
PD2/TIM3_ETR/UART5_RX/SDIO_CMD/DCMI_D11
116
PD3/FSMC_CLK/USART2_CTS
117
PD4/FSMC_NOE/USART2_RTS
118
PD5/FSMC_NWE/USART2_TX
119
PD6/FSMC_NWAIT/USART2_RX
122
PD7/USART2_CK/FSMC_NE1/FSMC_NCE2
123
PD8/FSMC_D13/USART3_TX
77
PD9/FSMC_D14/USART3_RX
78
PD10/FSMC_D15/USART3_CK
79
PD11/FSMC_A16/USART3_CTS
80
PD12/FSMC_A17/TIM4_CH1/USART3_RTS
81
PD13/FSMC_A18/TIM4_CH2
82
PD14/FSMC_D0/TIM4_CH3
85
PD15/FSMC_D1/TIM4_CH4
86
PE0/TIM4_ETR/FSMC_NBL0/DCMI_D2
141
PE1/FSMC_NBL1/DCMI_D3
142
PE2/TRACECK/FSMC_A23/ETH_MII_TXD3
1
PE3/TRACED0/FSMC_A19
2
PE4/TRACED1/FSMC_A20/DCMI_D4
3
PE5/TRACED2/FSMC_A21/TIM9_CH1/DCMI_D6
4
PE6/TRACED3/FSMC_A22/TIM9_CH2/DCMI_D7
5
PE7/FSMC_D4/TIM1_ETR
58
PE8/FSMC_D5/TIM1_CH1N
59
PE9/FSMC_D6/TIM1_CH1
60
PE10/FSMC_D7/TIM1_CH2N
63
PE11/FSMC_D8/TIM1_CH2
64
PE12/FSMC_D9/TIM1_CH3N
65
PE13/FSMC_D10/TIM1_CH3
66
PE14/FSMC_D11/TIM1_CH4
67
PE15/FSMC_D12/TIM1_BKIN
68
PF0/FSMC_A0/I2C2_SDA
10
PF1/FSMC_A1/I2C2_SCL
11
PF2/FSMC_A2/I2C2_SMBA
12
PF3/FSMC_A3/ADC3_IN9
13
PF4/FSMC_A4/ADC3_IN14
14
PF5/FSMC_A5/ADC3_IN15
15
PF6/TIM10_CH1/FSMC_NIORD/ADC3_IN4
18
PF7/TIM11_CH1/FSMC_NREG/ADC3_IN5
19
PF8/TIM13_CH1/FSMC_NIOWR/ADC3_IN6
20
PF9/TIM14_CH1/FSMC_CD/ADC3_IN7
21
PF10/FSMC_INTR/ADC3_IN8
22
PF11/DCMI_12
49
PF12/FSMC_A6
50
PF13/FSMC_A7
53
PF14/FSMC_A8
54
PF15/FSMC_A9
55
PG0/FSMC_A10
56
PG1/FSMC_A11
57
PG2/FSMC_A12
87
PG3/FSMC_A13
88
PG4/FSMC_A14
89
PG5/FSMC_A15
90
PG6/FSMC_INT2
91
PG7/FSMC_INT3/USART6_CK
92
PG8/USART6_RTS/ETH_PPS_OUT
93
PG9/USART6_RX/FSMC_NE2/FSMC_NCE3
124
PG10/FSMC_NCE4_1/FSMC_NE3
125
PG11/FSMC_NCE4_2/ETH_MII_TX_EN
126
PG12/FSMC_NE4/USART6_RTS
127
PG13/FSMC_A24/USART6_CTS/ETH_MII_TXD0/ETH_RMII_TXD0
128
PG14/FSMC_A25/USART6_TX/ETH_MII_TXD1/ETH_RMII_TXD1
129
PG15/USART6_CTS/DCMI_D13
132
PH0/OSC_IN
23
PH1/OSC_OUT
24
VBAT
6
VCAP_1
71
VCAP_2
106
VDDA
33
VDD_1
72
VDD_2
108
VDD_3
143
VDD_4
39
VDD_5
17
VDD_6
52
VDD_7
62
VDD_8
84
VDD_9
95
VDD_10
121
VDD_11
131
VDD_12
30
VDD_SA
144
VREF+
32
VSSA
31
VSS_2
107
VSS_4
38
VSS_5
16
VSS_6
51
VSS_7
61
VSS_8
83
VSS_9
94
VSS_10
120
VSS_11
130
U5
3
1
2
GND
VCC
RESET
U6
EN
1
FB
5
GND
2
IN
4
LX
3
U7
SY8008C(AA)C
BS
1
COMP
6
EN
7
FB
5
GND
4
IN
2
SS
8
SW
3
U8
1
2
3
4
5
6
7
8
9
10
UEXT
1
2
3
4
USB_HOST
D+
D-
GND
G
N
D
1
G
N
D
2
G
N
D
3
G
N
D
4
ID
VBUS
USB_OTG
WKUP
STM32-H407_Rev_B1
OLIMEX LTD PLOVDIV
http://www.olimex.com
+
+
+
+
+
GN D
0R
0R
0
R
P
O
W
E
R
A
N
A
LO
G
D
IG
IT
A
L
D
IG
IT
A
L
A
R
D
U
IN
O
: S
H
P
LA
T
F
O
R
M
U
S
B
SHIELD
U
S
B
POWER SUPPLY CIRCUIT
BUTTON and LED
JTAG
SD/MMC CARD
USB_HOST
USB_OTG
USART3_TX
USART3_RX
GND
USART3_RX
USART3_TX
