9.1 I/O接口扩展概述 9.1.1 扩展的I/O接口功能 9.1.2 I/O端口的编址 9.1.3 I/O数据的传送方式 9.1.4 I/O接口电路 9.2 AT89S52扩展I/O接口芯片82C55的设计 9.2.1 82C55芯片简介 9.2.2 工作方式选择控制字及端口PC置位/复位控制字 9.2.3 82C55的3种工作方式 9.2.4 单片机扩展82C55的接口设计 9.2.5 AT89S52扩展82C55的应用举例 9.3 利用74LSTTL电路扩展并行I/O口 9.4 用AT89S52单片机的串行口扩展并行口 9.4.1 用74LS165扩展并行输入口 9.4.2 用74LS164扩展并行输出口 9.5 用I/O口控制的声音报警接口 9.5.1 蜂鸣音报警接口 9.5.2 音乐报警接口

8.1 系统并行扩展结构 8.2 地址空间分配和外部地址锁存器 8.2.1 存储器地址空间分配 8.2.2 外部地址锁存器 8.3 静态数据存储器RAM的并行扩展 8.3.1 常用的静态RAM（SRAM）芯片 8.3.2 外扩数据存储器的读写操作时序 8.3.3 AT89S52单片机与RAM的接口设计与软件编程 8.4 片内Flash存储器的编程 8.4.1 使用通用编程器的程序写入 8.4.2 使用下载线的ISP编程 8.5 E2PROM的并行扩展 8.5.1 并行E2PROM芯片简介 8.5.2 E2PROM的工作方式 8.5.3 AT89S52单片机扩展E2PROM AT2864的设计

外研版（三起）（2012）小学英语五年级下册Module 7 Unit 2 I'll be home at seven o'clock.Module 7 Unit 2 I'll be home at seven o'clock.习题(1)

利用建立的用于强腐蚀性气氛高温腐蚀研究的连续称重测量装置,测定了Fe-25Cr铁素体合金在H2-H2S混合气氛中700~900℃及10-1~10-3Pa硫分压条件下的硫化行为。在经过初始孕育期之后,Fe-25Cr合金的硫化动力学符合分段抛物线规律。其腐蚀产物是双层结构:外层为品粒粗大的(FeCr)1-xS(x≈0.24.21at%~0at%Cr);内层是较薄的(CrFe)Sx(26.8at%Cr)等轴晶层。硫化过程受Fe,Cr离子向外扩散的控制

Unit 6 Day-to-day work 6.1 Talking about your work (1)Listening Listen to Ana Campos talking about her working hours. Are these statements true (T)or false(F)? 1 She starts works at 7.30. 2 She finishes work at 4.00 3 She has lunch at 12.00. 4 She has one hour for lunch. 5 She works a 40-hour week

Hera’s twin-brother Zeus sought her out at Cnossus in Crete, where he courted her, at first unsuccess￾fully. She took pity on him only when he adopted the disguise of a bedraggled cuckoo, and tenderly warm￾ed him in her bosom. There he at once resumed his true shape and ravished her, so that she was sham￾ed into marrying him

8.3.1 A/D转换器概述 8.3.2 A/D转换器的主要技术指标 8.3.3 AT89C51单片机与ADC0809接口应用 8.3.4 AT89C51与MC14433接口应用 8.4.1 D/A转换器的主要技术指标 8.4.2 D/A转换器与单片机的接口

Abstract In Chapter Seven we continue to look at the variety of ways in which people in Britain today spend their leisure time. We especially look at excursions away from home for a short or longer break. But we first look at the transport infrastructure of Great Britain a network of airports, railway lines, motorways and other roads, which, together, connect up the even remotest parts of the country and help to make

Problem set 3 Solutions Due: Tuesday, February 22 at 9 PM Problem 1. An urn contains 75 white balls and 150 black balls. while there are at least 2 balls remaining in the urn, you repeat the following operation. You remove 2 balls elected arbitrarily and then: If at least one of the two balls is black, then you discard one black ball and put the other ball back in the urn

6.8 Effect of Environment on Growth 6.9 Microbial Growth at ColdTemperatures 6.10 Microbial Growth at HighTemperatures 6.11 Microbial Growth at Low or High pH 6.12 Osmotic Effects on Microbial Growth 6.13 Oxygen and Microbial Growth