Computer & Electronics Engineering

Objectives

• Understand Digital Logic Gates

• Construct & Simulate Digital Logic Circuits on the Computer

Switches for Light ControlPage 13

Logic AND

0 0

1 0 1 1

0 1

AND Gate

A B OUT

0 0 0

0 1 0

1 0 0

1 1 1

1 0

Logic OR

0 0 0 1

1 1

OR GateA B OUT

0 0 0

0 1 1

1 0 1

1 1 1

Automotive Reminder System

• Key in Ignition (K)• Door Open (D) • Seatbelt Disconnected (S)• Headlights On (H)

Automotive Reminder System

• key AND door OR

• key AND seatbelt OR• light AND door OR

Automotive Reminder System Page 15

Automotive Reminder System Page 17

How to Use Electronics Workbench

Page 2

Build and test these circuits. Try to complete Circuits 1, 3, 5 & 6.

Circuit 1: Wiring Residential SwitchesCircuit 2: Switches as Logic ElementsCircuit 3: Automobile Buzzer SystemCircuit 5: Integrated Circuit Form of Automobile

Buzzer SystemCircuit 6: Binary Counter – Seven Segment DecoderCircuit 7: Two Digit Binary CounterCircuit 8: Simplified Binary CounterCircuit 9: Four Digit Binary Counter

Binary Count

B A Decimal

0 0 0

0 1 1

1 0 2

1 1 3

Binary Count

C B A Decimal

0 0 0 0

0 0 1 1

0 1 0 2

0 1 1 3

1 0 0 4

1 0 1 5

1 1 0 6

1 1 1 7

Binary

D C B A Decimal D C B A Decimal

0 0 0 0 0 1 0 0 0 8

0 0 0 1 1 1 0 0 1 9

0 0 1 0 2 1 0 1 0 10 (A)

0 0 1 1 3 1 0 1 1 11 (B)

0 1 0 0 4 1 1 0 0 12 ( C)

0 1 0 1 5 1 1 0 1 13 (D)

0 1 1 0 6 1 1 1 0 14 (E)

0 1 1 1 7 1 1 1 1 15 (F)

Binary Coded Decimal (BCD)

D C B A Decimal

0 0 0 0 0

0 0 0 1 1

0 0 1 0 2

0 0 1 1 3

0 1 0 0 4

0 1 0 1 5

0 1 1 0 6

0 1 1 1 7

1 0 0 0 8

1 0 0 0 9

7 Segment Displays

DCBA a b c d e f g0000 00001 10010 1 1 1 1 1 20011 30100 40101 50110 60111 71000 81001 9

Code Segments Digit

a

b

cde

f g

Display a “2”