根据图中的逻辑运算符号,包括与非逻辑(NAND)、或非逻辑(NOR)、与或非逻辑、异或逻辑(XOR)和同或逻辑(XNOR),我们可以分别给出每个运算符的真值表。
1. 与非逻辑(NAND)
A | B | A AND B | A NAND B |
---|---|---|---|
0 | 0 | 0 | 1 |
0 | 1 | 0 | 1 |
1 | 0 | 0 | 1 |
1 | 1 | 1 | 0 |
2. 或非逻辑(NOR)
A | B | A OR B | A NOR B |
---|---|---|---|
0 | 0 | 0 | 1 |
0 | 1 | 1 | 0 |
1 | 0 | 1 | 0 |
1 | 1 | 1 | 0 |
3. 与或非逻辑
假设与或非逻辑门包含两个“与”输入和一个“或非”操作,即 ( A ∧ B ) ∨ ( C ∧ D ) (A \land B) \lor (C \land D) (A∧B)∨(C∧D)的非。
A | B | C | D | A AND B | C AND D | (A AND B) OR (C AND D) | 与或非逻辑 |
---|---|---|---|---|---|---|---|
0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 |
0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 |
0 | 0 | 1 | 1 | 0 | 1 | 1 | 0 |
0 | 1 | 0 | 0 | 0 | 0 | 0 | 1 |
0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 |
0 | 1 | 1 | 0 | 0 | 0 | 0 | 1 |
0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 |
1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
1 | 0 | 0 | 1 | 0 | 0 | 0 | 1 |
1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 |
1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 |
1 | 1 | 0 | 0 | 1 | 0 | 1 | 0 |
1 | 1 | 0 | 1 | 1 | 0 | 1 | 0 |
1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
4. 异或逻辑(XOR)
A | B | A XOR B |
---|---|---|
0 | 0 | 0 |
0 | 1 | 1 |
1 | 0 | 1 |
1 | 1 | 0 |
5. 同或逻辑(XNOR)
A | B | A XNOR B |
---|---|---|
0 | 0 | 1 |
0 | 1 | 0 |
1 | 0 | 0 |
1 | 1 | 1 |
这些是不同门的真值表的详细内容,可以帮助您理解各个逻辑运算符在不同输入情况下的输出。
逻辑代数的基本公式是用于化简和操作布尔表达式的规则,常见的逻辑代数基本公式如下:
1. 恒等律
- A + 0 = A A+0=A A+0=A
- A ⋅ 1 = A A\cdot1=A A⋅1=A
2. 零和一律
- A + 1 = 1 A+1=1 A+1=1
- A ⋅ 0 = 0 A\cdot0=0 A⋅0=0
3. 互补律
- A + A ‾ = 1 A+\overline{A}=1 A+A=1
- A ⋅ A ‾ = 0 A\cdot\overline{A}=0 A⋅A=0
4. 双重否定律
- A ‾ ‾ = A \overline{\overline{A}}=A A=A
5. 幂等律
- A + A = A A+A=A A+A=A
- A ⋅ A = A A\cdot A=A A⋅A=A
6. 交换律
- A + B = B + A A+B=B+A A+B=B+A
- A ⋅ B = B ⋅ A A\cdot B=B\cdot A A⋅B=B⋅A
7. 结合律
- ( A + B ) + C = A + ( B + C ) (A+B)+C=A+(B+C) (A+B)+C=A+(B+C)
- ( A ⋅ B ) ⋅ C = A ⋅ ( B ⋅ C ) (A\cdot B)\cdot C=A\cdot(B\cdot C) (A⋅B)⋅C=A⋅(B⋅C)
8. 分配律
- A ⋅ ( B + C ) = ( A ⋅ B ) + ( A ⋅ C ) A\cdot(B+C)=(A\cdot B)+(A\cdot C) A⋅(B+C)=(A⋅B)+(A⋅C)
- A + ( B ⋅ C ) = ( A + B ) ⋅ ( A + C ) A+(B\cdot C)=(A+B)\cdot(A+C) A+(B⋅C)=(A+B)⋅(A+C)
9. 吸收律
- A + ( A ⋅ B ) = A A+(A\cdot B)=A A+(A⋅B)=A
- A ⋅ ( A + B ) = A A\cdot(A+B)=A A⋅(A+B)=A
10. 德摩根定律(De Morgan’s Laws)
- A ⋅ B ‾ = A ‾ + B ‾ \overline{A\cdot B}=\overline{A}+\overline{B} A⋅B=A+B
- A + B ‾ = A ‾ ⋅ B ‾ \overline{A+B}=\overline{A}\cdot\overline{B} A+B=A⋅B
11. 双重覆盖律
- A + A ‾ ⋅ B = A + B A+\overline{A}\cdot B=A+B A+A⋅B=A+B
- A ⋅ ( A ‾ + B ) = A ⋅ B A\cdot(\overline{A}+B)=A\cdot B A⋅(A+B)=A⋅B
12. 分配律的变形
- A ⋅ ( A + B ) = A A\cdot(A+B)=A A⋅(A+B)=A
- A + ( A ⋅ B ) = A A+(A\cdot B)=A A+(A⋅B)=A
这些公式用于逻辑表达式的化简、逻辑电路设计以及解决布尔代数问题。掌握这些规则,可以大大简化复杂的逻辑表达式并优化逻辑电路设计。