Question

A manual switch controlled 8-floor elevator is designed to operate such that when the master switch S=0, it moves up (0,1,2. . . ) and when the switch S=1, it moves down (7,6,5. . . ).

However, it has been observed that the elevator is experiencing the following problems:

1. When the S=1, the elevator instead of going down gets stuck on the current floor and does not move. (for example, if it is at the fourth floor, it remains there and does not move down).

2. When the switch is 0, the elevator goes up but skips the 2nd and 3rd floor.

Analyze the circuit and identify the problem and fix the issue.

Show the state table of the current design.

Show the state table of the new (fixed) elevator

Answer 1

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