Hands-On Embedded Programming with C++17

Adding an RTC

One can cheaply get RTCs as a ready-to-use module, often based around the DS1307 chip. This is a 5V module, which connects to the SBC (or MCU) via the I2C bus:

This image is of a small DS1307-based RTC module. As one can see, it has the RTC chip, a crystal, and an MCU. The last of these is used to communicate with the host system, regardless of whether it is an SoC or MCU-based board. All that one requires is the ability to provide the desired voltage (and current) the RTC module operates on, along with an I2C bus.

After connecting the RTC module to the SBC board, the next goal is to have the OS also use it. For this, we must ...