Solved–Homework Assignment 7– Solution

Description

You are going to write a complete C program which implements the following functionality:

• your program reads two files:

– circuit.txt

– input.txt

• According to content in circuit.txt, the program dynamically creates necessary structures for a logic circuit and evaluates the cases listed in input.txt.

• Your program prints the output to stdout. After each output there should be a newline.

circuit.txt

• Each line starts with a keyword. Possible keywords:

INPUT

AND

OR

NOT

FLIPFLOP

• The first line specifies input labels. Labels are separated by spaces. Exam-ple:

INPUT a input2 c3 k

• Here there are 4 inputs are defined. Each has an identifier. a, input2, c3, k.

• AND keyword specifies that there is an and gate defined. AND keyword follows the identifier for the gate and two other identifiers for the inputs. Example:

AND gate_A c3 another_id

• Here the and gate is identified by the string gate_A. Its inputs are identified c3 and another_id. These identifiers can be input identifiers or identifiers for other gates.

• OR keyword specifies that there is an or gate defined. OR keyword follows the identifier for the gate and two other identifiers for the inputs. Example:

OR gate_B ck id3

• Here the or gate is identified by the string gate_B. Its inputs are identified ck and id3. These identifiers can be input identifiers or identifiers for other gates.

• NOT keyword specifies that there is an not gate defined. NOT keyword follows the identifier for the gate and one other identifier for its input. Example:

NOT gate_C c5

• Here the not gate is identified by the string gate_C. It has only one input an it is identified by the string c5.

• FLIPFLOP keyword specifies that there is an flip-flop gate defined. FLIPFLOP keyword follows the identifier for the gate and one other identifier for its input. Example:

FLIPFLOP gate_F c6

• Here the flip-flop gate is identified by the string gate_F. Its input is identified by c6.

input.txt

• Each line is a list of 1 and 0. Example:

1011

0111

0010

1001

Example:

• Suppose that circuit.txt is has the following content:

INPUT a b c d

AND and1 a b

OR or1 and1 c

NOT n1 d

FLIPFLOP f1 n1

AND a2 or1 f1

• input.txt has the following content:

1101

1010

1110

• Assume that initially former-out of any FLIPFLOP is 0.

• Any FLIPFLOPs should preserve the state throughout the evaluation of the whole input.txt.

• Each line in input.txt is assigned to identifiers a, b, c, d, defined in circuit.txt. According to the truth tables, outputs of gates are calcu-lated.

• For the input.txt given, the output of your program should be:

0

1

0

Figure 1: Example Logic Circuit

Remarks

• Output is not defined explicitly. It is your job to figure out the output pin. There will always going to be one output pin.

• Each identifier is unique

• There won’t be any errors in the files.

• You have to use dynamical memory allocation and struct.

Turn in:

A complete C program <assignment_7_name_id.c> which can be compiled using the following command:

gcc -std=c99 assignment_7_name_id.c -o assignment_7_name_id

If your program requires additional compile and link options, state that require-ment at beginning of your source code as a comment.

Caution:

• Read and apply “Assignment Submission Rules and Other Related Infor-mation” document which available on the class e-learning system.

• You may or may not get partial credit depending on how you structured or documented your code.

Truth Tables:

• AND

a	b	out
0	0	0
0	1	0
1	0	0
1	1	1

• OR

a	b	out
0	0	0
0	1	1
1	0	1
1	1	1

• NOT

• out

• 1

1 0

• FLIPFLOP

a	former_out	out
0	0	0
0	1	1
1	0	1
1	1	0

4