3种基于HCS12定时器的PWM波形发生器的设计  

Three Designs of PWM Generator Based on HCS12 Timer

作　　者：冯道宁[1,2] 刘昭度[1] 叶阳[1] 

机构地区：[1]北京理工大学机械与车辆工程学院,北京100081 [2]广西机电职业技术学院电气工程系,南宁530007

出　　处：《武汉理工大学学报》2012年第2期140-143,共4页Journal of Wuhan University of Technology

基　　金：国家"十一五"预研项目(40401040302)

摘　　要：在车辆ASR系统开发中,提出了基于HCS12单片机增强型定时器复用I/O输出PWM信号的开发方案,解决了由于硬件限制导致PWM输出通道的不足的问题。介绍了单片机增强定时器通过输出比较寄存器、输出比较中断、TCNT输出翻转实现PWM波形输出的3种方法,详述了各方法中重要寄存器的设置和逻辑对应关系,并给出了相应的波形输出图和程序流程图,通过理论分析和实验结果探讨了不同设计方案的优缺点。The development of multiplex I/O output PWM waveform based on enhanced capture timer module of HSC12 single-chip is proposed in vehicle ASR system,to solves PWM output channels shortage due to hardware limitation led to the problem.Three approaches taken in the investigation is called output-compare register,interrupt caused by output-compare and TCNT output flip.Details of the methods set the single-chip registers and logical corresponding relation is introduced,the waveform output map and the procedure-flow chart is given.The character of different designs is proposed and the limitation is researched according to theory analysis the experimental results.

关 键 词：PWM 输出比较寄存器 占空比 TCNT 

分 类 号：TP368.12[自动化与计算机技术—计算机系统结构]