5.4 Code
Converter
It is a circuit
that converts one code to another, making two systems using different codes
compatible. To convert binary code A to binary code B, the input lines must
supply the bit combination of elements as specified by code A and the output
lines must generate the corresponding bit combination of code B.
Example
No. 1
Design a
combinational circuit that converts a decimal digit from the 8-4-2-1 code to
BCD code. Use NAND gates.
Solution
No.1
Make the Truth Table for the Problem.
Table 1. Truth table for example no 1
|
Decimal |
Inputs |
Output |
|||||||
|
|
A |
B |
C |
D |
V |
W |
X |
Y |
Z |
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
1 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
|
2 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
|
3 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
1 |
|
4 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
|
5 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
|
6 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
1 |
0 |
|
7 |
0 |
1 |
1 |
1 |
0 |
0 |
1 |
1 |
1 |
|
8 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
|
9 |
1 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
|
10 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
|
11 |
1 |
0 |
1 |
1 |
1 |
0 |
0 |
0 |
1 |
|
12 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
|
13 |
1 |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
1 |
|
14 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
|
15 |
1 |
1 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
Draw the Logic Circuits:
hint: Download this by
“right click” and “save as file” and then try it on the
simulator.