二、A/D和D/A的应用微机装置仅能对数字量进行处理,但生产过程中大量遇到的控制量是连续变化的物理量,它们的量值随时间作连续的变化,如温度、压力、流量、液位、位移、变形、成份等,它们经传感器后可生成对应的连续电压或电流。微机为了对这些模拟量进行处理,要经模拟——数字转换(A/D)来得到对应的数字量。处理结果如 Second, the application of A / D and D / A microcomputer device can only deal with the digital, but a lot of control in the production process is a continuous change in the amount of physical changes in their volume over time for continuous changes, such as temperature , Pressure, flow, level, displacement, deformation, composition, etc., which can be generated by the sensor after the corresponding continuous voltage or current. Microcomputer in order to deal with these analog, through the analog - digital conversion (A / D) to get the corresponding digital. For example,