I have seen many tutorials about connecting real time clock hardware on Orange Pi and Raspberry Pi.
What i didn't like was removing of fake-hwclock service, because I want that RTC works when it is connected, and fake-hwclock when RTC is not connected.
Therefore, I changed /sbin/fake-hwclock script to work in this way.
So, here is how to do this, tested on OrangePi+2E, Armbian Ubuntu legacy kernel:
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