A digital clock model decodes a 1 pulse per second input into seconds, minutes and hours; sixty seconds advance minutes, and sixty minutes advance hours. How do hours recycle back to one after 12?
A) The 1 for tens of hours and 2 for ones of hours is detected and resets hours back to zero.
B) The 2 is detected and resets the new tens and ones of hours to zero.
C) A MOD 6 counter automatically resets hours to zero.
D) The 1 for tens of hours and 2 for ones of hours is detected and resets hours back to 1 o'clock.

Question

Quizplus · Accepted Answer

The correct answer is D because in a 12-hour clock format, after reaching 12:59, the next increment would logically reset the clock to display 1:00, indicating the start of a new cycle. This is achieved by detecting the combination of 1 in the tens place and 2 in the ones place of the hour display and then resetting the hours to 1, not to zero.

A Digital Clock Model Decodes a 1 Pulse Per Second