we can simulate logic circuits like below:
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.
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 OUTPUT 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.
• 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