Waveshare E9 Hardware Manual page 18

On the front left of E9, the triangle part (in the right corner) is the 1 foot. Detailed features below:
NO. CPU
1 GND
2 5V
3 DP4
4 DP3
5 DM4
6 DM3
7 GND
8 3.3V
9 GPIO1_28
10 GPIO1_27
11 EIM_D17
12 EIM_D21
13 EIM_D16
14 EIM_D19
15 EIM_D30
16 EIM_D20
17 EIM_D18
18 CSI0_DATA10
19 SD1_CLK
20 SD3_RST
21 GPIO_5
22 GPIO_18
23 EIM_D22
24 EIM_D23
25 GPIO1_30
Shenzhen Waveshare Electronics Co., Ltd.
Descriptions
Ground
5V Power
3 works with 5,can be used as USB Host
4 works with 6,can be used as USB Host
3 works with 5,can be used as USB Host
4 works with 6,can be used as USB Host
Ground
3.3V Power
GPIO interface
GPIO interface
external interrupt 4, can be used as IO
external interrupt 5, can be used as IO
external interrupt 6(work with IrDA), can be used as IO
external interrupt 8, can be used as IO
external interrupt 16, can be used as IO or matrix keyboard
external interrupt 17, can be used as IO or matrix keyboard
external interrupt 18, can be used as IO or matrix keyboard
external interrupt 19, can be used as IO or matrix keyboard
external interrupt 20, can be used as IO or matrix keyboard
external interrupt 21, can be used as IO or matrix keyboard
external interrupt 22, can be used as IO or matrix keyboard
external interrupt 23, can be used as IO or matrix keyboard
external interrupt 24, can be used as IO or matrix keyboard
external interrupt 25, can be used as IO or matrix keyboard
external interrupt 26, can be used as IO or matrix keyboard
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