What will be the values of select inputs, carry-in input and result of operation if the following micro-operations are performed? – IGNOU MCA Assignment 2014 – 15

By | October 14, 2014

MASTER OF COMPUTER APPLICATIONS
Course Code : MCS-012
Course Title : Computer Organisation and Assembly Language Programming
Assignment Number : MCA (2)/012/Assign /2014-15
Maximum Marks : 100
Weightage : 25%

Assume that you have a machine as shown in section 3.2.2 of Block 3 having the micro-operations as given in Figure 10 on page 62 of Block 3. Consider that R1 and R2 both are 8 bit registers and contains 0001 1100 and 0111 1110 respectively. What will be the values of select inputs, carry-in input and result of operation (including carry out bit) if the following micro-operations are performed? (For each micro-operation you may assume the initial value of R1 and R2 as given above).

(i) Addition of R1 and R2

(ii) Exclusive OR of R1 and R2

(iii)Shift left R2 once

(iv) Decrement R1

(i) Addition of R1 and R2

 

S3

S2

S1

S0

Ci

F

Micro-operation

Name

0

0

0

1

0

F=x+y

R ß R1 + R2

Addition

 

 

0 0 0 1 1 1 0 0
0 1 1 1 1 1 1 0
1 0 0 1 1 0 1 0

 

S3

S2

S1

S0

Ci

F

Micro-operation

Name

Value of Result R

0

0

0

1

0

F=x+y

R ß R1 + R2

Addition

1001 1010

Micro-Operation_01  

 (ii) Exclusive OR of R1 and R2

S3

S2

S1

S0

Ci

F

Micro-operation

Name

0

1

1

0

-

F=x+y

R ß R1 + R2

Exclusive OR

 

 

0 0 0 1 1 1 0 0
0 1 1 1 1 1 1 0
0 1 1 0 0 0 1 0

 

S3

S2

S1

S0

Ci

F

Micro-operation

Name

Value of Result R

0

1

1

0

-

F=x+y

R ß R1 + R2

Exclusive OR

0110 0010

 Micro-Operation_02

 (iii)Shift left R2 once

S3

S2

S1

S0

Ci

F

Micro-operation

Name

1

0

-

-

-

F=Shl(x)

R ß Shl(R2)

Shift left

 

 

0 1 1 1 1 1 1 0
1 1 1 1 1 1 0 0

 

S3

S2

S1

S0

Ci

F

Micro-operation

Name

Value of Result R

1

0

-

-

-

F=Shl(x)

R ß Shl(R2)

Shift left

1111 1100

Micro-Operation_03

(iv) Decrement R1

S3

S2

S1

S0

Ci

F

Micro-operation

Name

0

0

-

-

-

F=x-1

R ß R1 - 1

Decrement

 

 

0 0 0 1 1 1 0 0
0 0 0 1 1 0 1 1

 

S3

S2

S1

S0

Ci

F

Micro-operation

Name

Value of Result R

0

0

-

-

-

F=x-1

R ß R1 - 1

Decrement

0001 1011

 

Micro-Operation_04