：热电阻在工业生产中常用于中低温区测温，是温度测量中应用较为普遍的测温元件．通过对其测 温原理的研究，设计了基于MSP430FI69单片机的热电阻测温仪．本设计采用恒流源驱动三线制热电 阻，配合信号平移、放大电路，利用片内A／D转换器，通过分时采样将热电阻对应的电压信号采集进来． 经过一阶插值拟合运算程序处理后显示温度值并由D／A转换器输出电压信号，再经过V-1变换实现 4—20 mA变送输出功能．-: Thermal resistance often used in indus

The HART Application Guide has been created by the HART Communication Foundation (HCF) to provide users of HART products with the information necessary to obtain the full benefits of HART digital instrumentation. The HART communication proto