CSE306 Assignment 1-Solved

Specification for 4-bit ALU Simulation
•   Required Flags:

–    Carry

–    Sign

–    Overflow

–    Zero

•   Flags will be affected as per the rules of Assembly Language.

•   Any SSI (AND, OR, NOT, XOR etc.) and MSI (MUX, Decoder, Adder etc.) chip can be used.

•   Emphasis should be given on efficiency of design and minimization of ICs used.

•   For simulation you can use any simulation software.

Appendix A

Functional design specifications for each group of each section

cs2 cs1 cs0
Functions for
Group 5
Group 6
0        0       0
Add
Decrement A
0        1       0
Transfer A
Subtract with borrow
1        0       0
Add with carry
Transfer A
1        1       0
Increment A
Subtract
x        0       1
OR
AND
x        1       1
Complement A
XOR
For Section A1

cin

cs2 cs1 cs0
 
Functions for
 
Group 1
Group 2
Group 3
Group 4
0        0       0
Add 
Decrement A
Subtract with borrow
Decrement A
0        0       1
Transfer A 
Subtract with borrow
Transfer A
Add
0        1       0
Add with carry 
Transfer A
Subtract
Transfer A
0        1       1
Increment A
Subtract
Increment A
Add with carry
1        x       0
AND
OR
AND
Complement A
1        x       1
XOR
Complement A
OR
XOR
 

cin

cs2 cs1 cs0
Functions for
Group 5
Group 6
0        0       0
Subtract with borrow
Decrement A
0        1       0
Transfer A
Add
1        0       0
Subtract
Transfer A
1        1       0
Increment A
Add with carry
x        0       1
OR
XOR
x        1       1
AND
Complement A
For Section A2

cin

cs2 cs1 cs0
 
Functions for
 
Group 1
Group 2
Group 3
Group 4
0        0       0
Add 
Decrement A
Subtract with borrow
Decrement A
0        0       1
Transfer A 
Subtract with borrow
Transfer A
Add
1        0       0
Add with carry 
Transfer A
Subtract
Transfer A
1        0       1
Increment A
Subtract
Increment A
Add with carry
x        1       0
AND
OR
AND
Complement A
x        1       1
XOR
Complement A
OR
XOR
 

cin

cs2 cs1 cs0
Functions for
Group 5
Group 6
0        0       0
Subtract with borrow
Decrement A
0        1       0
Subtract
Transfer A
0        x       1
OR
XOR
1        0       0
Transfer A
Add
1        1       0
Increment A
Add with carry
1        x       1
AND
Complement A
For Section B1

cin cs2 cs1 cs0
 
Functions for
 
Group 1
Group 2
Group 3
Group 4
0        0       0
Add 
Decrement A
Subtract with borrow
Decrement A
0        0       1
Add with carry 
Transfer A
Subtract
Transfer A
0        1       x
AND
OR
AND
Complement A
1        0       0
Transfer A 
Subtract with borrow
Transfer A
Add
1        0       1
Increment A
Subtract
Increment A
Add with carry
1        1       x
XOR
Complement A
OR
XOR
 

cin

cs2 cs1 cs0
Fu
nctions for
Group 5
Group 6
    0      0        0
Add
Decrement A
    0      1        0
Add with carry
Transfer A
    0      x        1
XOR
OR
    1      0        0
Transfer A
Subtract with borrow
    1      1        0
Increment A
Subtract
    1      x        1
AND
Complement A
For Section B2

cin cs2 cs1 cs0
 
Functions for
 
Group 1
Group 2
Group 3
Group 4
0        0       0
Add 
Decrement A
Subtract with borrow
Decrement A
0        0       1
Add with carry 
Transfer A
Subtract
Transfer A
0        1       0
Transfer A 
Subtract with borrow
Transfer A
Add
0        1       1
Increment A
Subtract
Increment A
Add with carry
1        0       x
OR
AND
OR
XOR
1        1       x
XOR
Complement A
AND
Complement A