求大神賜教如何改變下面程序pwm的輸出頻率（最好給出詳細(xì)的思路步驟）

ID:235126 · 發(fā)表于 2017-10-14 17:34

#include "reg51.h"

#define CYCLE 0x1000L    //定義PWM周期(最大值為32767)
#define DUTY 10L       //定義占空比為10%

#define PWMC       (*(unsigned int  volatile xdata *)0xfff0)
#define PWMCH    (*(unsigned char volatile xdata *)0xfff0)
#define PWMCL    (*(unsigned char volatile xdata *)0xfff1)
#define PWMCKS    (*(unsigned char volatile xdata *)0xfff2)
#define PWM2T1    (*(unsigned int  volatile xdata *)0xff00)
#define PWM2T1H    (*(unsigned char volatile xdata *)0xff00)
#define PWM2T1L    (*(unsigned char volatile xdata *)0xff01)
#define PWM2T2    (*(unsigned int  volatile xdata *)0xff02)
#define PWM2T2H    (*(unsigned char volatile xdata *)0xff02)
#define PWM2T2L    (*(unsigned char volatile xdata *)0xff03)
#define PWM2CR    (*(unsigned char volatile xdata *)0xff04)
#define PWM3T1    (*(unsigned int  volatile xdata *)0xff10)
#define PWM3T1H    (*(unsigned char volatile xdata *)0xff10)
#define PWM3T1L    (*(unsigned char volatile xdata *)0xff11)
#define PWM3T2    (*(unsigned int  volatile xdata *)0xff12)
#define PWM3T2H    (*(unsigned char volatile xdata *)0xff12)
#define PWM3T2L    (*(unsigned char volatile xdata *)0xff13)
#define PWM3CR    (*(unsigned char volatile xdata *)0xff14)
#define PWM4T1    (*(unsigned int  volatile xdata *)0xff20)
#define PWM4T1H    (*(unsigned char volatile xdata *)0xff20)
#define PWM4T1L    (*(unsigned char volatile xdata *)0xff21)
#define PWM4T2    (*(unsigned int  volatile xdata *)0xff22)
#define PWM4T2H    (*(unsigned char volatile xdata *)0xff22)
#define PWM4T2L    (*(unsigned char volatile xdata *)0xff23)
#define PWM4CR    (*(unsigned char volatile xdata *)0xff24)
#define PWM5T1    (*(unsigned int  volatile xdata *)0xff30)
#define PWM5T1H    (*(unsigned char volatile xdata *)0xff30)
#define PWM5T1L    (*(unsigned char volatile xdata *)0xff31)
#define PWM5T2    (*(unsigned int  volatile xdata *)0xff32)
#define PWM5T2H    (*(unsigned char volatile xdata *)0xff32)
#define PWM5T2L    (*(unsigned char volatile xdata *)0xff33)
#define PWM5CR    (*(unsigned char volatile xdata *)0xff34)
#define PWM6T1    (*(unsigned int  volatile xdata *)0xff40)
#define PWM6T1H    (*(unsigned char volatile xdata *)0xff40)
#define PWM6T1L    (*(unsigned char volatile xdata *)0xff41)
#define PWM6T2    (*(unsigned int  volatile xdata *)0xff42)
#define PWM6T2H    (*(unsigned char volatile xdata *)0xff42)
#define PWM6T2L    (*(unsigned char volatile xdata *)0xff43)
#define PWM6CR    (*(unsigned char volatile xdata *)0xff44)
#define PWM7T1    (*(unsigned int  volatile xdata *)0xff50)
#define PWM7T1H    (*(unsigned char volatile xdata *)0xff50)
#define PWM7T1L    (*(unsigned char volatile xdata *)0xff51)
#define PWM7T2    (*(unsigned int  volatile xdata *)0xff52)
#define PWM7T2H    (*(unsigned char volatile xdata *)0xff52)
#define PWM7T2L    (*(unsigned char volatile xdata *)0xff53)
#define PWM7CR    (*(unsigned char volatile xdata *)0xff54)

sfr PIN_SW2 = 0xba;

sfr P0M1 = 0x93;
sfr P0M0 = 0x94;
sfr P1M1 = 0x91;
sfr P1M0 = 0x92;
sfr P2M1 = 0x95;
sfr P2M0 = 0x96;
sfr P3M1 = 0xb1;
sfr P3M0 = 0xb2;
sfr P4M1 = 0xb3;
sfr P4M0 = 0xb4;
sfr P5M1 = 0xC9;
sfr P5M0 = 0xCA;
sfr P6M1 = 0xCB;
sfr P6M0 = 0xCC;
sfr P7M1 = 0xE1;
sfr P7M0 = 0xE2;

sfr PWMCFG  = 0xf1;
sfr PWMCR = 0xf5;
sfr PWMIF = 0xf6;
sfr PWMFDCR = 0xf7;

void main()
{
P0M0 = 0x00;
P0M1 = 0x00;
P1M0 = 0x00;
P1M1 = 0x00;
P2M0 = 0x00;
P2M1 = 0x00;
P3M0 = 0x00;
P3M1 = 0x00;
P4M0 = 0x00;
P4M1 = 0x00;
P5M0 = 0x00;
P5M1 = 0x00;
P6M0 = 0x00;
P6M1 = 0x00;
P7M0 = 0x00;
P7M1 = 0x00;

PIN_SW2 |= 0x80;             //使能訪(fǎng)問(wèn)XSFR
PWMCFG = 0x00;                //配置PWM的輸出初始電平為低電平
PWMCKS = 0x00;                //選擇PWM的時(shí)鐘為Fosc/(0+1)
PWMC = CYCLE;                //設(shè)置PWM周期
PWM2T1 = 0x0000;             //設(shè)置PWM2第1次反轉(zhuǎn)的PWM計(jì)數(shù)
PWM2T2 = CYCLE * DUTY / 100; //設(shè)置PWM2第2次反轉(zhuǎn)的PWM計(jì)數(shù)
                                 //占空比為(PWM2T2-PWM2T1)/PWMC
PWM2CR = 0x00;                //選擇PWM2輸出到P3.7,不使能PWM2中斷
PWMCR = 0x01;                //使能PWM信號(hào)輸出
PWMCR |= 0x80;                //使能PWM模塊
PIN_SW2 &= ~0x80;

while (1);
}

ID:111634 · 發(fā)表于 2017-10-15 21:14

本帖最后由 zl2168 于 2017-10-15 21:17 編輯

介紹你一個(gè)參考案例

直流電機(jī)正反轉(zhuǎn)及PWM調(diào)速
先Proteus仿真一下，確認(rèn)有效。

實(shí)例100 直流電機(jī)正反轉(zhuǎn)及調(diào)速.rar (44.12 KB, 下載次數(shù): 33)

以上摘自張志良編著《80C51單片機(jī)仿真設(shè)計(jì)實(shí)例教程——基于Keil C和Proteus》清華大學(xué)出版社ISBN 978-7-302-41682-1，內(nèi)有常用的單片機(jī)應(yīng)用100案例，用于仿真實(shí)驗(yàn)操作，電路與程序真實(shí)可靠可信可行。書(shū)中電路和程序設(shè)計(jì)有詳細(xì)說(shuō)明，程序語(yǔ)句條條有注解。仿真電路和Hex文件能在清華出版社網(wǎng)站免費(fèi)下載，程序源代碼只能到書(shū)上看了。到圖書(shū)館借，或到新華書(shū)店翻閱，或到網(wǎng)上書(shū)店打折購(gòu)買(mǎi)。

ID:235126 · 發(fā)表于 2017-10-16 20:12

zl2168 發(fā)表于 2017-10-15 21:14
介紹你一個(gè)參考案例
直流電機(jī)正反轉(zhuǎn)及PWM調(diào)速
先Proteus仿真一下，確認(rèn)有效。

多謝答主解答

帳號(hào)		自動(dòng)登錄	找回密碼
密碼			立即注冊(cè)

求大神賜教如何改變下面程序pwm的輸出頻率（最好給出詳細(xì)的思路步驟）

瀏覽過(guò)的版塊