新手入门
- 积分
- 17
- 金钱
- 17
- 注册时间
- 2016-6-7
- 在线时间
- 4 小时
|
5金钱
手头这块开发板是STM32F107VC的,TIM1引脚重映射到GPIO口如下:
PE9-------->TIM1_CH1
PE11------->TIM1_CH2
PE13------->TIM1_CH3
PE14------->TIM1_CH4
PE9、11、13、14每个都对应一个LED,我尝试用正点原子的程序移植过来产生PWM控制LED的亮度变化
但一直不成功,下载程序后LED都亮,但并没有亮度变化
虽然不想当伸手党,但搞了好一阵子了还是没搞出来,发帖请教
(我用的不是正点原子的开发板,不了解这里的规矩,不知道这样可不可以提问,不可以的话我自行删帖)
正点原子的程序是用的TIM3,是普通定时器,TIM1是高级定时器,我另外也对TIM_BDTRInitStructure进行了设置
我把我的完整项目文件上传在附件里,另外贴一下main.c 、timer.c、LED.c 三个文件里的相关代码,刚接触STM32不长时间,一定是哪里写的不对,望前辈指教!
main.c
[mw_shl_code=c,true]
#include "led.h"
#include "delay.h"
#include "key.h"
#include "sys.h"
#include "usart.h"
#include "timer.h"
//ALIENTEK战舰STM32开发板实验9
//PWM输出实验
//技术支持:www.openedv.com
//广州市星翼电子科技有限公司
int main(void)
{
u16 led0pwmval=0;
u8 dir=1;
delay_init(); //延时函数初始化
NVIC_Configuration(); //设置NVIC中断分组2:2位抢占优先级,2位响应优先级
// uart_init(9600); //串口初始化为9600
// LED_Init(); //LED端口初始化
TIM1_PWM_Init(899,0); //不分频。PWM频率=72000/900=8Khz
while(1)
{
delay_ms(10);
if(dir)led0pwmval++;
else led0pwmval--;
if(led0pwmval>300)dir=0;
if(led0pwmval==0)dir=1;
TIM_SetCompare2(TIM1,led0pwmval);
}
}[/mw_shl_code]
timer.c
[mw_shl_code=c,true]#include "timer.h"
#include "led.h"
#include "usart.h"
//通用定时器1中断初始化
//这里时钟选择为APB1的2倍,而APB1为36M
//arr:自动重装值。
//psc:时钟预分频数
//这里使用的是定时器1!
void TIM1_Int_Init(u16 arr,u16 psc)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE); //时钟使能
TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值 计数到5000为500ms
TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值 10Khz的计数频率
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
TIM_ITConfig(TIM1,TIM_IT_Update,ENABLE ); //使能指定的TIM1中断,允许更新中断
NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_IRQn; //TIM1中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级0级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //从优先级3级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure); //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器
TIM_Cmd(TIM1, ENABLE); //使能TIMx外设
}
void TIM1_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure; //定义结构体GPIO_InitStructure
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; //定义结构体TIM_TimeBaseStructure
TIM_OCInitTypeDef TIM_OCInitStructure; //定义结构体TIM_OCInitStructure
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB2Periph_TIM1,ENABLE); //使能定时器1时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO|RCC_APB2Periph_GPIOE,ENABLE); //使能复用时钟、使能GPIOE的时钟
GPIO_PinRemapConfig(GPIO_PartialRemap_TIM1,ENABLE); //TIM1部分重映射使能,映射端口为TIM1_CH1、2、3、4分别对应GPIOE9、11、13、14
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9|GPIO_Pin_11|GPIO_Pin_13|GPIO_Pin_14;
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP; //GPIO推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOE,&GPIO_InitStructure);
TIM_TimeBaseStructure.TIM_Period = arr; //设置自动重装载值
TIM_TimeBaseStructure.TIM_Prescaler = psc; //设置预分频值
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS=Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数模式
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM1,&TIM_TimeBaseStructure); //根据指定的参数初始化TIM1
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择PWM模式2(为什么选择模式2?)
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_Pulse = 200; //TIM_Pulse设置了待装入捕获比较寄存器的脉冲值——占空比为50%(why?)
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性高
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High; //why?
TIM_OC1Init(TIM1,&TIM_OCInitStructure); //初始化TIM1 OC1,从TIM1_CH1输出PWM
TIM_OC1PreloadConfig(TIM1,TIM_OCPreload_Enable); //使能预装载寄存器
TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 0x90; //调整死区大小0-0xFF
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
TIM_BDTRConfig(TIM1,&TIM_BDTRInitStructure);
TIM_Cmd(TIM1,ENABLE); //使能TIM1
TIM_CtrlPWMOutputs(TIM1,ENABLE);
}
//定时器1中断服务程序
void TIM1_IRQHandler(void) //TIM1中断
{
if (TIM_GetITStatus(TIM1, TIM_IT_Update) != RESET) //检查指定的TIM中断发生与否:TIM 中断源
{
TIM_ClearITPendingBit(TIM1, TIM_IT_Update ); //清除TIMx的中断待处理位:TIM 中断源
LED1=!LED1;
}
}
[/mw_shl_code]
LED.c
[mw_shl_code=c,true]#include "led.h"
void LED_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOE, ENABLE); //使能PB,PE端口时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //LED0-->PB.9 端口配置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //IO口速度为50MHz
GPIO_Init(GPIOE, &GPIO_InitStructure); //根据设定参数初始化GPIOB.5
GPIO_SetBits(GPIOE,GPIO_Pin_9); //PB.5 输出高
}
[/mw_shl_code]
|
|