The BIGTREETECH CB1 uses a custom IO pinout for the pins which consists of PA, PB….PG and a number. To calculate a GPIO Number, you need to use the following formula:

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[(PG - PA)*32] + {Pin Number}
Where PA = 1, PB =2….so PG = 7

So if you want to calculate PG19, then it would be ((7-1)*32) + 19 = 211 = GPIO211. Potentially also this lookup table  might help.

The pins of the 40-pin connector are listed here already - maybe that helps to quickly get the right numbers ;-)

References

• https://github.com/So6Rallye/BTT-Pi/blob/018930134b72f43b6b4b242ffafca145bdffbc87/BIGTREETECH%20Pi%20V1.2%20-%20Board%20Fan%20Pin%20Configuration 

Solution

There are different solutions for this but the following one worked the best for me:

First remove NTP:

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sudo apt remove ntp

and install the systemd-native timesync service:

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sudo apt install systemd-timesyncd

This should automatically install the service and start it. To make sure, you can check that systemd-timesyncd.service is active (running):

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systemctl status systemd-timesyncd

And when using:

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timedatectl status

you should see something like:

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System clock synchronized: yes
              NTP service: active

References

• https://askubuntu.com/a/1373363 

GPIO stands for General-Purpose Input/Output. It refers to the pins on a microcontroller or single-board computer, like the Raspberry Pi, that can be programmed to serve as either inputs or outputs. These pins enable the device to interact with the external world by receiving or transmitting digital signals. Through software programming, developers can configure GPIO pins to read data from sensors (inputs) or send signals to actuators (outputs), facilitating versatile applications like the control of fans, lights or other 3D printing accessories.

Thankfully the pinout is the same on the Manta M4P which is why i was able to extract the data from there  (page 9):

BIGTREETECH describes the pinout of the CM4 the same as the one of the Raspberry pi. However when being used with the CB1, the Pinout Changes. I extracted that information and then used various sources of research to find the corresponding GPIO port: This is the final result:

Update: Now i finally found a mapping in the CB1 repo - check there  if you want to see the mapping for the BTT PI or CB1 MMC version.