Chapter 6: Q9E (page 500)
Implement the four-input odd-parity function with a PLA.
Short Answer
To implement a four-input odd parity function with PLA, the AND operation is performed on 0000, 0011, 0101, 0110, 1001, 1010, 1100, and 1111. The OR operation on the output of eight AND gates give the correct result.
Step by step solution
Definition of PLAs
PLAs are programmable logic devices used to implement combinational logic circuits. It is a fixed architecture logic device with programmable AND gates followed by programmable Or gates.
Identify the truth table for a four-input odd-parity function
The parity bit is one if there are even numbers of 1s in the input. Otherwise, it is zero. The truth table is given below:
Data bit 4 (D4) | Data bit 3 (D3) | Data bit 2 (D2) | Data bit 1 (D1) | Parity bit |
0 | 0 | 0 | 0 | 1 |
0 | 0 | 0 | 1 | 0 |
0 | 0 | 1 | 0 | 0 |
0 | 0 | 1 | 1 | 1 |
0 | 1 | 0 | 0 | 0 |
0 | 1 | 0 | 1 | 1 |
0 | 1 | 1 | 0 | 1 |
0 | 1 | 1 | 1 | 0 |
1 | 0 | 0 | 0 | 0 |
1 | 0 | 0 | 1 | 1 |
1 | 0 | 1 | 0 | 1 |
1 | 0 | 1 | 1 | 0 |
1 | 1 | 0 | 0 | 1 |
1 | 1 | 0 | 1 | 0 |
1 | 1 | 1 | 0 | 0 |
1 | 1 | 1 | 1 | 1 |
Implementation of four-input odd-parity function
The following diagram shows the implementation of the four-input odd-parity function using PLA:
Over 30 million students worldwide already upgrade their learning with Vaia!
