Question

Design state machines to control the minutes and hours of a standard 24 hour clock. Your clock should include an AM/PM indicator light, 2-digit hours (1 – 12), 2-digit minutes (00 – 59). (There is no need to include seconds; if we wanted to display seconds, it would be the same state control unit as minutes.)

Answer 1

Answer:

1 Hz clock generator to produce 1 PPS (beat every second) sign to the seconds square.

SECONDS square - contains a partition by 10 circuit followed by a gap by 6 circuit. Will produce a 1 PPM (beat every moment) sign to the minutes square. The BCD yields associate with the BCD to Seven Segment circuit to show the seconds esteems.

MINUTES square - indistinguishable from the seconds square it contains 2 dividers; a partition by 10 followed by a separation by 6. Will produce a 1 PPH (beat every hour) sign to the HOURS square. The BCD yields interfaces with the BCD to Seven Segment circuit to show the minutes esteems.

HOURS square - relying upon whether it is a 12 or 24H clock, will have a partition 24 or separation by 12. For 24H, it will tally from 00 to 23. For 12H, it will tally from 00 to 11. The BCD yields associates with the BCD to Seven Segment circuit to show the hours esteems.

Note that: To rearrange the table, K is Q0 of IC1 (ones), G is Q0 of IC2 (tens, etc.

For the 12H clock, when the include in BCD comes to

0A, IC1 must be cleared (Y=1)

12, IC1 must be cleared (Y=1) and IC2 must be cleared (X=1)

Utilizing SOP (entirety of items), we get

Y = HJ + GJ where Y is the IC1 MR1, MR2 inputs associated together.

X = GJ where X is the IC2 MR1, MR2 inputs associated together.

Explanation: