交流电量采集板的设计

介绍了交流电量采集板的硬件结构及软件设计．硬件结构中较有特色的部分是利用锁相环来自动校正采样周期，使精度得到进一步提高．在总线接口部分，利用并行I／O接口芯片8255A构成查询与应答相结合的通信方式，使采集板与STD总线机之间的通信可靠．不易出现死锁现象，在软件设计中，采用模块式结构，使软件程序调试方便，并引入了看门狗定时器，避免因故障时出现死锁．

Design of Alternating Current Quantity Sampling Plate

This paper introduces the hardware structure and the software design about AC data acquisition board. The characteristic part in the hardware structure the use of phase-locked loop to correct automatically sampling instant in order to enhance the accuracy degree further. In the bus interface circuit, we use parallel I/O interface chip 8255a to ac complish the work in ask-and-answer communication manner. With this method, the communication is of high reliability and is not easy dead-locked. In the software design, we use block structure in order to debug program conveniently. Meanwhile we use watch dog timer to avoid dead-locking caused by failure.