7.1 数/模（D/A）转换 7.2 模/数（A/D）转换 7.3 数/模、模/数通道设计

6.1 可编程并行I/O接口8255A 6.2 串行通信和串行I/O接口 6.3 可编程串行I/O接口8251A

5.1 中断控制器8259A 5.2 DMA控制器8237A 5.3 定时/计数器8253

A/D 转换器是将模拟信号转换为数字信号，转换过程通过采样、保持、量化和编码四个步骤完成

New Words dedicate:give, devote(one's time, energy, life, etc. to a noble cause or purpose If you dedicate yourself to something you decide to give a lot of time and effort to it because you think it is important

数字通信系统具有许多优点。然而许多信源输出都是模拟信号。 若要利用数字通信系统传输模拟信号,一般需三个步骤: (1)把模拟信号数字化,即模数转换(A/D); (2)进行数字方式传输; (3)把数字信号还原为模拟信号,即数模转换(D/A) 由于A/D或D/A变换的过程通常由信源编(译)码器实现,所以我们把发端 的A/D变换称为信源编码,而收端的D/A变换称为信源译码,如语音信号的数字 化叫做语音编码

1.1用真值表证明下列恒等式 (1)⊕B=A⊙B=AB1 (2)A(B⊕C)=AB⊕AC (3)(A+B)(A+C)(B+C)=(a+B)(a+C)

Chapter Four Computer Technology Chapter Study Tasks (4) In this chapter, you will be able to -Explain why a computer is a system

2.1过程参数采样原理 2.2模拟量输入通道 2.3D/A、A/D转换技术 2.4模拟量输出通道

22 Semiconductors G.S. Gildenblat, B. Gelmont, M. Milkovic, A. Elshabini-Riad, F.W. Stephenson, I.A. Bhutta, D.C. Look Physical Properties. Diodes. Electrical Equivalent Circuit Models and Device Simulators for Semiconductor Devices Electrical Characterization of Semiconductors