连接方式：
Sensor SCL <-> I2C0_SCK (PIN 22)
Sensor SDA <-> I2C0_SDA (PIN 23)
Sensor GND <-> pin 21 GND
Sensor VCC <-> pin 27 3.3V
tail /boot/env.txt
i2c3 – Enable i2c3 (GPIO Header PIN22 & PIN23)
spi1 – Enable SPI1 (GPIO Header PIN15 & PIN16 & PIN35 & PIN37), pwm_f need to be removed
i2s – Enable I2S (GPIO Header PIN29 & PIN30 & PIN31 & PIN32 & PIN33)
os08a10 – Enable OS08A10 Camera
onewire – Enable onewire bus (GPIO Header PIN15)
disable-ts050 – Disable TS050 LCD
m2x-eth – Enable M2X 100M ethernet. Note: 1G ethernet will be disabled.
otg-device – Enable USB OTG Device
watchdog – Enable watchdog
overlays=uart3 pwm_f i2c3 i2s os08a10 watchdog
检测结果：
root@Khadas:/home/khadas# i2cdetect -y 3
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: – – – – – – – – – – – – –
10: – – – – – – – – – – – – – – – –
20: – – – – – – – – – – – – – – – –
30: – – – – – – – – – – – – – – – –
40: – – – – – – – – – – – – – – – –
50: – – – – – – – – – – – – – – – –
60: – – – – – – – – – – – – – – – –
70: – – – – – – – –
root@Khadas:/home/khadas# i2cdetect -y 4
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: – – – – – – – – – – – UU –
10: – – – – – – – – UU – – – – – – –
20: UU – 22 – – – – – – – – – – – – –
30: – – – – – – – – – – – – – – – –
40: – – – – – – – – – – – – – – – –
50: – UU – – – – – – – – – – – – – –
60: – – – – – – – – – – – – UU – – –
70: – – – – – – – –
我的线是接在/dev/i2c-3，为何 i2cdetect -y 3 输出没反应呢?