嵌入式系统外围接口电路的复杂可编程逻辑器件实现

CPLD Realization of Embedded System Peripheral I/O Interface

为简化PCB布板,增强系统功能,提高系统的速度、抗干扰性、可靠性,提出一种用Altera公司CPLD芯片EPM7128S实现MCU外围接口电路的方法.在环境监测仪的MCU外围接口电路中,根据其功能结构与宏单元特点,利用VerilogHDL硬件描述语言和MAXplus-II设计工具软件,在单片CPLD上设计了MCU与A/D转换芯片、Flash Mem-ory、LCD及键盘4个模块的接口电路.对各个模块进行了编译、综合和仿真.实验表明,在一片CPLD芯片EPM7128S上,可实现多种接口功能,简化接口硬件连接,提高译码速度,编程方便灵活.

In this paper,a realization of embedded system peripheral I/O interface based on Altera CPLD EPM7218S is proposed. The CPLD is used for simplifying PCB layout, enhancing system function,improving system＇s speed, anti-jamming and reliability. In the instrument design for detecting environment parameter,four interface circuit module are realized in a single CPLD which based on EPM7128＇s function structure and macrocell feature. Four module are MCU and A/D chip, MCU and Flash Memory, MCU and LCD, MCU and keyboard. Each module has been programmed ,synthesized and emulated. By experiment,the result indicate in a EMP7128S it can achieve several interface functions, make hardware interface connection facility, improve coding speed, make program more convenient.