MCU port
Signal name
CN19 pin number
Signal name
MCU port
PB8
LCD_B6
33
34
GND
-
PB9
LCD_B7
35
36
NRST
NRST
PH6
-
GND
37
38
I2C4_SDA
PF15
PG2
CTP_INT
39
40
I2C4_SCL
PF14
-
NC
41
42
NC
-
PG15
LCD_BL_CTRL
43
44
NC
-
-
5V
45
46
NC
-
-
GND
47
48
NC
-
-
GND
49
50
3V3
-
1. The default configuration is shown in bold.
8.9
CN3 Ethernet RJ45 connector
The
board supports 10Mbps/100Mbps Ethernet communications with the U9 MICROCHIP
LAN8742A-CZ-TR PHY, and the CN3 integrated RJ45 connector. The Ethernet PHY is connected to the
STM32H735IGK6 microcontroller through an RMII interface.
The PHY 25 MHz clock is generated from the X1 oscillator, while the STM32H735IGK6 50 MHz clock is
generated by the PHY RMII_REF_CLK.
Figure 18.
CN3 Ethernet RJ45 connector
The related pinout for the Ethernet connector is listed in
Table 20.
CN3 Ethernet connector pinout
Connector
Pin number
Description
Pin number
Description
CN3
1
TX+
7
NC
2
TX-
8
NC
3
RX+
9
Cathode yellow LED
4
NC
10
Anode yellow LED
5
NC
11
Cathode green LED
6
RX-
12
Anode green LED
UM2679
CN3 Ethernet RJ45 connector
UM2679
-
Rev 1
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