AVR单片机+CPLD体系在测频电路中的应用

Application of AVR MCU and CPLD in Frequency Measurement Circuit

在测频电路中,其系统单片机与CPLD硬件接口采用独立工作方式。系统上电复位后,CPLD接收经过处理的待测频信号,并通过内部脉冲计数模块得到时间数据,然后通过与AVR单片机相联的14位端口,把时间数据传给AVR单片机。AVR单片机将数据存储并计算处理后,传给数码管,完成数据的动态扫描显示。

An independent work mode was used in the system MCU and CPLD hardware interface in a frequency measurement circuit. After the system was powered on and reset, CPLD received the being measured frequency signal which, and the signal was handled was converted into the time data by the inner pulse counter module of the CPLD. Then, the time data was sent to the AVR MCU via the fourteen ports between the CPLD and the AVR MCU. The time data was stored and computed by the AVR MCU, and then was sent it to nixie tube. So the dynamic scan display was finished.