A Real Time Clock chip provides the best possible long term accuracy for the clock. Its possible to mount the required parts directly on the board. Alternatively, you can just plug in the rtcBoB (from Wyolum) or the pin compatible Chronodot from Macetech.
If you intend to just plug in the rowBoB or Chronodot, just install 4 pin male headers CD1 and CD2.
If you wish to mount the rtc components directly on the main board, we assume you know how to read a schematic.
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