![](https://github.com/Ricolxwz/Computer-Organization-408/raw/main/Computer-Organization%20WD/Data%20representation%20and%20operation/SVG/Circuit%20Fundamentals%20&%20Adder%20Design1.drawio.svg)
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$A(C+D)=AC+AD$ --- 分配律
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$ABC=A(BC)$ --- 结合律
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$A+B+C=A+(B+C)$ --- 结合律
$Y=A·B$
A |
B |
Y |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
1 |
$Y=A+B$
A |
B |
Y |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
1 |
$Y=\overline{A}$
- $\overline{A+B}=\overline{A}\cdot \overline{B}$
- $\overline{A\cdot B}=\overline{A}+\overline{B}$
$Y=\overline{A·B}$
A |
B |
Y |
0 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
0 |
$Y=\overline{A+B}$
A |
B |
Y |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
$Y=A⊕B=\overline{A}\cdot B+A\cdot \overline{B}$
A |
B |
Y |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
0 |
$Y=A⊙B$
A |
B |
Y |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
1 |
![](https://github.com/Ricolxwz/Computer-Organization-408/raw/main/Computer-Organization%20WD/Data%20representation%20and%20operation/SVG/Circuit%20Fundamentals%20&%20Adder%20Design3.drawio.svg)
$A_i, B_i, C_{i-1}$
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$S_i=A_i⊕B_i⊕C_{i-1}$: 输入有奇数个1时为1(异或)
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$C_i=A_iB_i+(A_i⊕B_i)C_{i-1}$: 输入中至少2个1(两个为都是1或者两个本位中有一个是1, 且来自低位的进位是1)
![](https://github.com/Ricolxwz/Computer-Organization-408/raw/main/Computer-Organization%20WD/Data%20representation%20and%20operation/IMG/Circuit%20Fundamentals%20&%20Adder%20Design2.png)
![](https://github.com/Ricolxwz/Computer-Organization-408/raw/main/Computer-Organization%20WD/Data%20representation%20and%20operation/SVG/Circuit%20Fundamentals%20&%20Adder%20Design4.drawio.svg)
- 只有一个全加器, 数据逐位串行送入加法器中进行运算. 进位触发器用来寄存进位信号, 以便参与下一次运算.
- 如果操作数长n位, 加法就要分为n次进行, 每次产生一位和, 并且串行逐位送回寄存器
![](https://github.com/Ricolxwz/Computer-Organization-408/raw/main/Computer-Organization%20WD/Data%20representation%20and%20operation/SVG/Circuit%20Fundamentals%20&%20Adder%20Design5.drawio.svg)
- 把n个全加器串接起来, 就可进行两个n位数的相加
- 串行进位又称为行波进位, 每一级进位直接依赖于前一级的进位, 即进位信号是逐级形成的