Logic Gates
Logic gates are the fundamental building blocks of digital circuits, and are critical to the functioning of basic computer functions. They are responsible for processing binary data in a computer by performing Boolean logic operations such as AND, OR, NOT, and XOR. By combining multiple logic gates, complex digital circuits can be created that can perform a wide range of operations, from basic arithmetic to complex decision-making processes.
AND
Boolean multiplication corresponds to the logical function of an “AND” gate, as well as to series switch contacts:
OR
Boolean addition corresponds to the logical function of an “OR” gate, as well as to parallel switch contacts:
NOT
Boolean complementation finds equivalency in the form of the NOT gate, or a normally-closed switch or relay contact:
Half-Adder Circuit
A half-adder circuit is used to add two bits of data together and is based on the following Truth Table.
A | B | Sum | Carry |
---|---|---|---|
0 | 0 | 0 | 0 |
1 | 0 | 1 | 0 |
0 |
Correct! |
1 | 0 |
1 | 1 | 0 |
Correct! |
A half-adder circuit consists of two logic gates as follows:
Full-Adder Circuit
A full-adder circuit is used to add three bits of data together and is based on the following Truth Table.
A | B | C in | Sum | Cout |
---|---|---|---|---|
0 | 0 | 0 | 0 | 0 |
1 | 0 | 0 | 1 | 0 |
0 | 1 | 0 | 1 | 0 |
1 | 1 | 0 |
Correct! |
1 |
0 | 0 | 1 | 1 | 0 |
1 | 0 |
Correct! |
0 | 1 |
0 | 1 | 1 | 0 | 1 |
1 | 1 | 1 | 1 |
Correct! |
A full-adder circuit consists of two half-adder circuits and an OR gate connected as follows:
Hacks
Answer these questions in your blog:
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How can logic gates be used to execute basic computer functions?(1-2 sentences)
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What is the difference between boolean operations and logic gates?(1-2 sentences)
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Go to this link and complete the following game. Take a screenshot of when you’ve completed it. Talk about how each logic gate works with one another.