Questions:

$1.$ An automation engineer has designed a system to control a garden watering system. The watering system can be activated manually or by a timer, provided that a moisture sensor indicates the soil is dry.

The structure of the circuit will be as shown below:

a$.$ Write the name the logic gates you have used:

GATE X

GATE Y

GATE Z

b$.$ Draw the logic circuit using appropriate logic gates. Note that the output of the moisture sensor is $`1`($true$,$ high, on$)$ when the soil is wet. The watering system must activate only when the soil is dry.

c$.$ Redraw the logic circuit above, and determine the logic states of all inputs and outputs for the following scenario:

It is a dry day, the manual switch is off, and the timer is off. Will the watering system be activated?

d$.$ Write the truth table for the entire system.

$2.$ Design a universal shift register which can shift left, right or parallel depending of selection switch condition.

Answers: