串口发送接收都正常，但是pwm输出的小灯就是不亮

草帽 · 发表于 2015-7-14 15:45:55

自己定的一个通信协议头：0x02 尾是0x04 中间数据是 P W M _ _ _;

主函数：

[mw_shl_code=c,true]#include "timer.h"[/mw_shl_code] [mw_shl_code=c,true]#include "usart.h" #include "delay.h" //#include "led.h" int main(void) { u16 led0pwmval=0; u8 t; uart_init(9600); delay_init(); //LED_Init(); TIM3_PWM_Init(899,0); NVIC_Configuration(); while(1) { if(USART_RX_BUF[USART_RX_STA]==0x04) { for(t=0;t<USART_RX_STA;t++) { USART_SendData(USART1,USART_RX_BUF[t]); while(USART_GetFlagStatus(USART1,USART_FLAG_TC)!=SET); } } printf("\r\n\r\n");//???????? USART_RX_STA=0; if(flag==1) { if(USART_RX_BUF[0]=='P'&&USART_RX_BUF[1]=='W'&&USART_RX_BUF[2]=='M') { led0pwmval=((USART_RX_BUF[3]&0xf)<<8)|((USART_RX_BUF[4]&0xf)<<4)|(USART_RX_BUF[5]&0xf); TIM_SetCompare2(TIM3,led0pwmval); } } flag=0; printf("\r\n??·???????:\r\n\r\n"); delay_ms(1000); } } [/mw_shl_code]

USART.c

[mw_shl_code=c,true]#include "sys.h" #include "usart.h" #if 1 #pragma import(__use_no_semihosting) //±ê×????è?????§?????? struct __FILE { int handle; }; FILE __stdout; //?¨??_sys_exit()??±???????°??÷?ú???? _sys_exit(int x) { x = x; } //???¨??fputc???? int fputc(int ch, FILE *f) { while((USART1->SR&0X40)==0);//???··???,?±??·????ê±? USART1->DR = (u8) ch; return ch; } #endif /*????microLib??·?·¨*/ /* int fputc(int ch, FILE *f) { USART_SendData(USART1, (uint8_t) ch); while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET) {} return ch; } int GetKey (void) { while (!(USART1->SR & USART_FLAG_RXNE)); return ((int)(USART1->DR & 0x1FF)); } */ #if EN_USART1_RX //?????????????? //?®??1????·??????ò //×???,????USARTx->SR??±??????????????í?ó u8 USART_RX_BUF[USART_REC_LEN]; //????????,×??óUSART_REC_LEN??×???. //????×??? //bit15?? ?????ê??±ê?? //bit14?? ??????0x0d //bit13~0?? ???????????§×??????? u16 USART_RX_STA=0; //????×???±ê?? u8 flag=0; void uart_init(u32 bound){ //GPIO?????è?? GPIO_InitTypeDef GPIO_InitStructure; USART_InitTypeDef USART_InitStructure; NVIC_InitTypeDef NVIC_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //????USART1??GPIOA?±?? //USART1_TX PA.9 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //???????ì???? GPIO_Init(GPIOA, &GPIO_InitStructure); //USART1_RX PA.10 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//???????? GPIO_Init(GPIOA, &GPIO_InitStructure); //Usart1 NVIC ???? NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//??????????3 NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //×???????3 NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ?¨?????? NVIC_Init(&NVIC_InitStructure); //?ù?????¨????????????VIC?????÷ //USART ???????è?? USART_InitStructure.USART_BaudRate = bound;//??°??è????9600; USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×??¤??8?????????? USART_InitStructure.USART_StopBits = USART_StopBits_1;//?????????? USART_InitStructure.USART_Parity = USART_Parity_No;//?????????é?? USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//???????????÷???? USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //??·????? USART_Init(USART1, &USART_InitStructure); //???????®?? USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//???????? USART_Cmd(USART1, ENABLE); //?????®?? } void USART1_IRQHandler(void) //?®??1????·??????ò { u8 Res; if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //????????(????????????±?????0x0d 0x0a?á??) { Res =USART_ReceiveData(USART1);//(USART1->DR); //???????????????? if(Res==0x02) { USART_RX_BUF[0]=Res; USART_RX_STA=0; } if(Res==0x04) //±í???????????ê??,flag??1?? { USART_RX_BUF[USART_RX_STA]=Res; flag=1; } if(Res!=0x02&&Res!=0x04) { USART_RX_STA++; USART_RX_BUF[USART_RX_STA]=Res; } } } #endif [/mw_shl_code]

timer.c

[mw_shl_code=c,true]#include "timer.h" void TIM3_PWM_Init(u16 arr,u16 psc) { GPIO_InitTypeDef GPIO_InitStructure; TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //?????¨?±?÷3?±?? RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE); //????GPIO???è??AFIO???????????é?±?? GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3, ENABLE); //Timer3??·??????? TIM3_CH2->

B5 //?è??????????????????????,????TIM3 CH2??PWM?????¨?? GPIOB.5 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5; //TIM_CH2 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //???????ì???? GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOB, &GPIO_InitStructure);//??????GPIO //??????TIM3 TIM_TimeBaseStructure.TIM_Period = arr; //?è???????????ü??????×°????????×?????×°???????÷???????? TIM_TimeBaseStructure.TIM_Prescaler =psc; //?è??????×÷??TIMx?±?????????????¤·????? TIM_TimeBaseStructure.TIM_ClockDivision = 0; //?è???±??·???:TDTS = Tck_tim TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM?ò?????????? TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //?ù??TIM_TimeBaseInitStruct?????¨????????????TIMx???±???ù?????? //??????TIM3 Channel2 PWM???? TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //?????¨?±?÷????:TIM?????í???÷??????2 TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //±??????????? TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //????????:TIM????±????????? TIM_OC2Init(TIM3, &TIM_OCInitStructure); //?ù??T???¨???????????????èTIM3 OC2 TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); //????TIM3??CCR2?????¤×°???????÷ TIM_Cmd(TIM3, ENABLE); //????TIM3 } [/mw_shl_code]