嵌入式系统与PLC

嵌入式系统与PLCprogrammable controller &embedded system

嵌入式系统

理论

特点：面向特定的应用，空间和资源相对不足，需要高效率设计used for specific application，storage space and resource is insufficient，should be high efficiency designed软件固化software solidified有相应的开发工具和环境relevant programming tool and environment成本低 low cost

与单片机的区别：单片机系统也属于嵌入式系统，可视为低端嵌入式系统single-chip microcomputer is also embedded system，but in low standard。嵌入式系统设计的核心是软件设计，约占70%的工作量，单片机系统软硬件设计工作所占比例基本相同the core of embedded system design is software，nearly 70%

组成

处理器核

GPIO

ADC、DAC

timer

存储器 storage：FLash、SDRAM、SRAM、EEPROM

电源 power source

时钟 clock

分类

冯•诺依曼体系结构Von Neumann architecture

存储器存储数据和指令 storage store instruct and data

哈佛结构Harvard architecture

分别有程序存储器和数据存储器

Micro Control UnitDigital Signal ProcessorMicro Processor Unit

STM32STM32F103ZET6

串口线 和电脑连接Serial Port Line

keils 5

144 feet512 flashclock 72MHz112 IO8 timer3 ADC（12bit） 2 DAC（12bit）68interruption 20 outside interruption

实验

LCD屏幕显示

LED、nixie tube display

PLC

型号：FX2N 32MR 16 I/O\tAC power source\tDC INPUT Relay output

Programmable Logic Controller 也是嵌入式系统，结构与一半计算机相似，but for special purpose

rich recourse can direct connect with equipment high voltage large currenteasy programmingmostly used in automatic control

红绿灯