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． The hardware structure and software design of AC power acquisition board are introduced. The more distinctive part of the hardware structure is the use of phase-locked loop to automatically correct the sampling period, the accuracy has been further improved. In the bus interface part, the parallel I / O interface chip 8255A is used to form a combination of inquiry and response, which ensures reliable communication between the acquisition board and the STD bus. Not prone to deadlock phenomenon, the software design, modular structure, the software program debugging convenience, and the introduction of the watchdog timer to avoid deadlock due to failure.