Assignment 4 Logic circuit simulator.

CSE 241 Programming Assignment 4
Description
• If you think that this document does not clearly describes the assignment, ask questions before its too late.
This assignment is about implementing and testing classes for a logic circuit simulator.
• Your program reads two files:
– circuit.txt
– input.txt
• According to content in circuit.txt, the program dynamically creates necessary objects for a logic circuit
and evaluates the states listed in input.txt.
• Your program prints the output to stdout. Each line in input.txt is a state. For each state, there should be
a line of output printed.
circuit.txt
• Each line starts with a keyword. Possible keywords:
INPUT
AND
OR
NOT
FLIPFLOP
DECODER
• The first line specifies input labels. Labels are separated by spaces. Example:
INPUT a input2 c3 k
• Here there are 4 inputs are defined. Each has an identifier. a, input2, c3, k.
• The second line specifies output labels. Labels are separated by spaces. Example:
OUTPUT d1 d2 d3 d4
• Here there are 4 outputs are defined. Each has an identifier. d1, d2, d3, d4.
• AND keyword specifies that there is an and gate defined. AND keyword follows the identifier for its output and
two other identifiers for the inputs. Example:
AND gate_A c3 another_id
• Here the and gate has an output 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 its output and two
other identifiers for the inputs. Example:
OR gate_B ck id3
• Here the or gate has an output identified by the string gate_B. Its inputs are identified ck and id3. These
identifiers can be input identifiers or identifiers for other gates.
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• NOT keyword specifies that there is a not gate defined. NOT keyword follows the identifier for its output and
one other identifier for its input. Example:
NOT gate_C c5
• Here the not gate has an output 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 a flip-flop gate defined. FLIPFLOP keyword follows the identifier
for its output and one other identifier for its input. Example:
FLIPFLOP gate_F c6
• Here the flip-flop gate has an output identified by the string gate_F. Its input is identified by c6.
• DECODER keyword specifies that there is a decoder gate defined. DECODER keyword follows the identifiers for
its outputs(o1, o2, o3, o4) and identifiers for its inputs(a1, a2). Example:
DECODER d1 d2 d3 d4 g1 another_identifier
• Here the decoder gate has outputs identified by strings o1, o2, o3, o4. Its inputs are identified by g1 and
another_identifier.
input.txt
• Each line is a list of 1 and 0. Example:
1 0 1 1
0 1 1 1
0 0 1 0
1 0 0 1
Example:
• Suppose that circuit.txt is has the following content:
INPUT a b c d
OUTPUT d1 d2 d3 d4
AND and1 a b
OR or1 and1 c
NOT n1 d
FLIPFLOP f1 n1
AND a2 or1 f1
DECODER d1 d2 d3 d4 a2 f1
• input.txt has the following content:
1 1 0 1
1 0 1 0
1 1 1 0
• 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 calculated.
• For the input.txt given, the output of your program should be:
1 0 0 0
0 0 0 1
1 0 0 0
2
and1 or1
a
b
c
d
f1
a2
n1 d1
d2
d3
d4
and
gate or
gate
and
flip gate
flop not
gate decoder
Figure 1: Example Logic Circuit
Remarks
• Each identifier is unique. You can assume that their length is limited to 15 characters. You can use
std::string.
• There won’t be any errors in the files.
• You have to use dynamic memory allocation and C++ classes.
• You have use inheritance and polymorphism. Find a class hierarchy and try to use abstraction.
• You are not allowed to used std::vectors.
• You cannot use components which are not covered in class. (such as templates etc..)
• In order to learn about file I/O operations, you can go through the related book chapter(not covered in class).
Or you can read the section presented in assignment 3.
Turn in:
• Source code of a complete C++ program and a suitable makefile. You should use c++11 standard. Your code
will be tested in a linux-gcc environment.
• A script will be used in order to check the correctness of your results. So, be careful not to violate the expected
output format.
• Provide comments unless you are not interested in partial credit. (If I cannot easily understand your design,
you may loose points.)
• You cannot get full credit if your implementation contradicts with the statements in this document.
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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
a out
0 1
1 0
• FLIPFLOP
a former_out out
0 0 0
0 1 1
1 0 1
1 1 0
• DECODER
a1 a2 d1 d2 d3 d4
0 0 0 0 0 1
0 1 0 0 1 0
1 0 0 1 0 0
1 1 1 0 0 0
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