Hello everyone,
I’m trying also to connect the RTC ds1307 in RockPi4C+, but it isn’t detecting by I2C.

Informations:

• RTC ds1307 used: https://www.seeedstudio.com/Pi-RTC-DS1307.html
• Armbian OS version: 25.2
• Kernel version: 6.12.10-current-rockchip64
• i2c-7 enabled on armbian-config (> System > Kernel > SY210 > rockchip-rk3399-i2c7)
• When I run the command: sudo i2cdetect -y 7 shows the error Error: Could not open file /dev/i2c-7' or /dev/i2c/7’: No such file or directory
• When I run the command: sudo i2cdetect -l shows:
• i2c-0 i2c rk3x-i2c I2C adapter
• i2c-3 i2c rk3x-i2c I2C adapter

Is someone can help to solve this problem?

Thanks

Check /boot/armbianEnv.txt

 

overlays=i2c1 i2c2 rockchip-rk3399-i2c7

 

 

Try this instead:

overlays=i2c1 i2c2 rk3399-i2c7

 

I changed the  /boot/armbianEnv.txt with overlays=i2c1 i2c2 rk3399-i2c7 but it continues without detect i2c-7 or i2c-1. 

Can you provide me with the output of  ls /boot/dtb/rockchip/overlay ?

It already detected i2c-7.

I think the problem was in the line  "overlay_prefix=rockchip", it was commented in the file /boot/armbianEnv.txt.

 

After that, the i2c-7 already detected, but the rtc module doesn't set datetime when the rock4cplus boots without Internet. 

 

Do you have any suggestion?

 

Thank you for your help.

No clue, sorry. I never actually used i2c

It started working after running the following commands:

 

sudo modprobe rtc-ds1307
 

echo ds1307 0x68 | sudo tee /sys/class/i2c-adapter/i2c-7/new_device

 

Thank you for help.