基于现场总线的单片机温度测量系统.doc

目 录 1， 绪论 ···································································3 1.1 设计总体说明···························································4 1.2方案论证·······························································7 1.2.1 铂热电阻·······························································7 1.2.2　ＡＴ８９Ｓ５１······························································7 1.2.3 现场总线······························································8 总体设计·································································13 2.1系统工作原理···················································13 2.2系统方框图····························································14 2.3系统总体电路设计·····················································15 3、硬件设计·······························································15 3.1总体设计框架··························································15 3.2温度传感器····························································16 3.2.1传感器概述························································16 3.2.2传感器的静态特性·················································17 3.2.3传感器的动态特性·················································20 3.2.4传感器不失真检测转换条件········································20 3.2.5传感器的分类······················································21 3.2.6电阻式温度传感器··················································22 3.2.7传感器的选用······················································23 3.3 A/D转换器····························································23 3.3.1 A/D转换器的类型·················································23 3.3.2 ADC性能指标·····················································24 3.3.3选用ADC0809·····················································25 3.4单片机·································································28 3.4.1单片机概述························································28 3.4.2 AT89S51单片机····················································29 3.5 CAN总线设计·········································