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There are three interrupts that the real time clock can generate and these are TICK (200 times a second - 5ms), SEC (once a second) and MIN (once a minute). TSTA may be set for all three events at once, or individually (all at once means that a TICK made a new second and that second made a minute).
STA.TIME is also set when TSTA.MIN /SEC/or TSTA.SEC or TSTA.TICK are set according TMK mask. When all TSTA interrupts have been acknowledged, STA.TIME is reset by Blink. This logic is detailed in blink interrupt.
Three registers are associated with these interrupts:
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