2009年9月26日 第5章_Memory extension IO extension 双语教学_黄英_《单片机原理及应用》讲义.pptVIP

Chapter 5 :  Memory extension   I/O extension Contents: 5.3.2 Typical Extension Chip of Data Memory 6116（2KB×8）: 211 → A10~A0 6264（8KB×8）: 213 → A12~A0 Pins Arrangement of SRAM 6116（2KB×8） 2. Working Modes of SRAM 6116 4 types: · Read · Write · Unselect · Forbidden Return 5.3.3 Examples of Extension Data Memory 1. Single Chip Expanding Contents: 2. Multi-Chip Expanding Return · 6116（2KB×8） 211 → A10～A0 → 23×28 → P2.2～P2.0 → P0.7～P0.0 1. Single Chip Expanding * Microcontroller Principle and Application 主讲教师：黄英 5.1 Memory extension introduction 5.2 Program memory extension Chapter 5 Memory extension I/O extension 5.3 Data memory extension 5.4 I/O extension introduction 5.5 I/O interface chip: 8255 5.6 Keyboard interface 5.7 LED Displayer interface Home work （1） Home work （2） 5.1 Memory extension introduction 5.1.1 System extension its structure 5.1.2 Memory extension addresses arrangement Contents: Return 5.1.1 System extension and it’s structure 1. Structure of system extension 2. System Bus its construction method Contents: Return · Extension objects: ROM, RAM, I/O interface circuit, etc. Fig. 1 The structure of system extension 1. Structure of system extension · In order to realize system extension, the first thing is: to construct system bus Return 2. System Bus its construction method （1）System Bus · System Bus is divided into three groups: AB、DB、CB ① Address Bus（AB） · Carry address information. · Single direction: MCU → Memory, I/O interface · Its number determines the number of memory cells: · Maximal extension space: n → 2n 216 cells = 64KB ② Data Bus（DB） · Carry data information · Bi-direction: MCU ? Memory, I/O interface · Bit number: Word number（8 bits） ③ Control Bus（CB） · Carry control information · Bi-direction : MCU → Memory, I/O interface （2）System Bus Construction · Address Bus: