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在网上参考了两个人的思想原理后动工，3天内搞定!其实也就是ds2408的工作原理，参考文献列出如下： 在STM32上通过UART+DMA实现One-Wire总线 http://www./module/forum/thread-581885-1-1.html http://wenku.baidu.com/link?url=aJy-AA_isWC-JtFKPAz58Gq3avNilMHlcRkRY3WK-cSDvqXB-CRuR_VSzNF6zYIr7ZMEPA4ifpwSef2J9SXpT1wVN_FA3Ak0udloV4JpByO 主要参考了第一个文献，第二个文献作为原理说明。 贴出代码前有问题要说明一下，就是其实第三天最后的时间就浪费在一个很小的细节上，就是温度转换时间在12位时为750ms，如果发出温度转换命令后立马去读取暂存器是读不出正确温度， 第三条的晚上差点就犯了这错误，几乎就要放弃了。已经都寻找到了替代方案，就是TC1047+ADC的方式，可是后来一想又心有不甘，明明原理上是对的，怎么就出不来呢！所以恒心在这里还是很重要的，一瞬间，一想到这点，随便改了两下代码，把发出温度转换命令后再读取温度前加了个延时就搞定了！ 很抱歉代码从keil v5中贴出来是中文注释全部都乱码了，先不管它，以后养成英语注释的习惯，顺便解决下keil 对中文支持不好的问题。下面是主代码DS18B20.c #include "ds18b20.h" #include <stdio.h> #include "led.h" u8 dmabuffer[8]={1,2,3,4,5,6,7,8}; bool DS18B20_Rst(void) { u8 revdat; uart3_init(36,9600); while(USART3->SR&(1<<5)) USART3->SR&=0xffff-1<<5; USART3->SR&=0xff-(1<<6); USART3->SR&=0xff-(1<<5); USART3->CR1|=1<<2;//?óê?ê1?ü USART3->CR1|=1<<3;//·￠?íê1?ü USART3->SR&=0xff-(1<<6); USART3->DR=0xf0; while((USART3->SR&0X40)==0);//μè′y·￠?ííê3é USART3->SR&=0xffff-(1<<6); while(USART3->SR&(1<<5)==0);//μè′y?óê?±ê????1 revdat=USART3->DR&0xff; //printf("%x",revdat); uart3_init(36,115200); return revdat!=0xf0; } void bytetobit(u8 byte,u8* bits ) { u8 j; for (j=0;j<8;j++) { if(byte&(1<<j)) *bits=0xff; else *bits=0x00; bits++; } } u8 bitstobyte(u8* bits) { u8 i; u8 byte=0; for(i=0;i<8;i++) { if(*bits==0xff) byte|= (1<<i);//μí???ú?° bits++; } return byte; } u16 j=0; void dma_transffer() { USART3->SR&=0xff-(1<<6); USART3->SR&=0xff-(1<<5); USART3->CR3|=1<<6;//ê1?üDMA?óê? USART3->CR3|=1<<7;//ê1?üDMA·￠?í USART3->CR1|=1<<2;//?óê?ê1?ü USART3->CR1|=1<<3;//·￠?íê1?ü DMA1->IFCR|=1<<4; DMA1->IFCR|=1<<8; MYDMA_Enable(DMA1_Channel2); MYDMA_Enable(DMA1_Channel3); while((DMA1->ISR & 1<<5) ==0);//μè′yDMA?óê?íê3é DMA1_Channel2->CCR&=~(1<<0); //1?±?DMA DMA1_Channel3->CCR&=~(1<<0); // printf("%d",DMA1_Channel2->CNDTR); USART3->CR3&=0xff-1<<6;//1?±?uart dmaí¨μà USART3->CR3&=0xff-1<<7; //for (j=0;j<8;j++) //printf("%d",dmabuffer[j]); } //D′ò???×??úμ?DS18B20 //dat￡oòaD′è?μ?×??ú void writebyte(u8 dat) { bytetobit(dat,dmabuffer); dma_transffer(); } void Write_Buffer(u8* buf,u8 length) { while(length--) { writebyte(*buf); buf++; } } u8 readbyte() { bytetobit(0xff,dmabuffer ); dma_transffer(); return bitstobyte(dmabuffer); } void Read_Buffer(u8* buf,u8 length) { while(length--) { *buf=readbyte(); buf++; } } //′óds18b20μ?μ????è?μ //???è￡o0.1C //·μ???μ￡o???è?μ ￡¨-550~1250￡? short DS18B20_Get_Temp(void) { u8 temp; u8 TL,TH; short tem; DS18B20_Rst(); Write_Buffer("\xCC\x44",2); // ds1820 start convert delay_ms(500); DS18B20_Rst(); Write_Buffer("\xCC\xbe",2); // ds1820 read data TL=readbyte(); // LSB TH=readbyte(); // MSB if(TH>7) { TH=~TH; TL=~TL; temp=0;//???è?a?o }else temp=1;//???è?a?y tem=TH; //??μ???°??? tem<<=8; tem+=TL;//??μ?μ×°??? tem= tem>>6;//×a??*0.0625?íê?3yó?16?àμ±óúóòò?4?? 2??ao?1ê???èéy??á?4±? if(temp)return tem; //·μ?????è?μ else return -tem; } 下面随便也把一些外设驱动代码贴出来，主要是串口配置和DMA配置的 #include "sys.h" #include "usart.h" //V1.3DT???μ?÷ //?§3?êêó|2?í??μ?ê??μ?′??ú2¨ì??êéè??. //?óè?á???printfμ??§3? //???óá?′??ú?óê??üá?1|?ü. //DT?yá?printfμúò???×?·??aê§μ?bug ////////////////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////// //?óè?ò???′ú??,?§3?printfoˉêy,??2?Dèòa????use MicroLIB #if 1 #pragma import(__use_no_semihosting) //±ê×??aDèòaμ??§3?oˉêy struct __FILE { int handle; /* Whatever you require here. If the only file you are using is */ /* standard output using printf() for debugging, no file handling */ /* is required. */ }; /* FILE is typedef?ˉ d in stdio.h. */ FILE __stdout; //?¨ò?_sys_exit()ò?±ü?aê1ó?°??÷?ú?￡ê? _sys_exit(int x) { x = x; } //???¨ò?fputcoˉêy int fputc(int ch, FILE *f) { while((USART1->SR&0X40)==0);//?-?··￠?í,?±μ?·￠?ííê±? USART1->DR = (u8) ch; return ch; } #endif //end ////////////////////////////////////////////////////////////////// #ifdef EN_USART1_RX u8 USART_RX_BUF[64]; u8 USART_RX_STA=0; void USART1_IRQHandler(void) { u8 res; if(USART1->SR&(1<<5))//????? { res=USART1->DR; if((USART_RX_STA&0x80)==0)//????? { if(USART_RX_STA&0x40)//????0x0d { if(res!=0x0a)USART_RX_STA=0;//????,???? else USART_RX_STA|=0x80; //????? }else //????0X0D { if(res==0x0d)USART_RX_STA|=0x40; else { USART_RX_BUF[USART_RX_STA&0X3F]=res; USART_RX_STA++; if(USART_RX_STA>63)USART_RX_STA=0;//??????,?????? } } } } } #endif #ifdef EN_USART3_RX //è?1?ê1?üá??óê? //′??ú1?D??·t??3ìDò //×￠òa,?áè?USARTx->SR?ü±ü?a?a??????μ?′í?ó u8 USART_RX_BUF[64]; //?óê??o3?,×?′ó64??×??ú. //?óê?×′ì? //bit7￡??óê?íê3é±ê?? //bit6￡??óê?μ?0x0d //bit5~0￡??óê?μ?μ?óDD§×??úêy?? u8 USART_RX_STA=0; //?óê?×′ì?±ê?? void USART3_IRQHandler(void) { u8 res; if(USART3->SR&(1<<5))//?óê?μ?êy?Y { res=USART3->DR; if((USART_RX_STA&0x80)==0)//?óê??′íê3é { if(USART_RX_STA&0x40)//?óê?μ?á?0x0d { if(res!=0x0a)USART_RX_STA=0;//?óê?′í?ó,??D??aê? else USART_RX_STA|=0x80; //?óê?íê3éá? }else //?1??ê?μ?0X0D { if(res==0x0d)USART_RX_STA|=0x40; else { USART_RX_BUF[USART_RX_STA&0X3F]=res; USART_RX_STA++; if(USART_RX_STA>63)USART_RX_STA=0;//?óê?êy?Y′í?ó,??D??aê??óê? } } } } } #endif //3?ê??ˉIO ′??ú1 //pclk2:PCLK2ê±?ó?μ?ê(Mhz) //bound:2¨ì??ê //CHECK OK //091209 void uart3_init(u32 pclk2,u32 bound) { float temp; u16 mantissa; u16 fraction; temp=(float)(pclk2*1000000)/(bound*16);//μ?μ?USARTDIV mantissa=temp; //μ?μ???êy2?·? fraction=(temp-mantissa)*16; //μ?μ?D?êy2?·? mantissa<<=4; mantissa+=fraction; RCC->APB2ENR|=1<<3; //ê1?üPORTB?úê±?ó RCC->APB1ENR|=1<<18; //ê1?ü′??ú3ê±?ó GPIOB->CRH=0X44444f44;//IO×′ì?éè?? // GPIOB->CRH&=0XFFFF00FF; // GPIOB->CRH|=0X00004b00; RCC->APB1RSTR|=1<<18; //?′??′??ú3 RCC->APB1RSTR&=~(1<<18);//í￡?1?′?? //2¨ì??êéè?? USART3->BRR=mantissa; // 2¨ì??êéè?? USART3->CR1|=0X200C; //1??í￡?1,?TD￡?é??. #ifdef EN_USART3_RX //è?1?ê1?üá??óê? //ê1?ü?óê??D?? USART3->CR1|=1<<8; //PE?D??ê1?ü USART3->CR1|=1<<5; //?óê??o3???·????D??ê1?ü MY_NVIC_Init(3,3,USART3_IRQChannel,2);//×é2￡?×?μíó??è?? #endif } void uart1_init(u32 pclk2,u32 bound) { float temp; u16 mantissa; u16 fraction; temp=(float)(pclk2*1000000)/(bound*16);//??USARTDIV mantissa=temp; //?????? fraction=(temp-mantissa)*16; //?????? mantissa<<=4; mantissa+=fraction; RCC->APB2ENR|=1<<2; //??PORTA??? RCC->APB2ENR|=1<<14; //?????? GPIOA->CRH=0X444444B4;//IO???? RCC->APB2RSTR|=1<<14; //????1 RCC->APB2RSTR&=~(1<<14);//???? //????? USART1->BRR=mantissa; // ????? USART1->CR1|=0X200C; //1???,????. #ifdef EN_USART1_RX //??????? //?????? USART1->CR1|=1<<8; //PE???? USART1->CR1|=1<<5; //??????????? MY_NVIC_Init(3,3,USART1_IRQChannel,2);//?2,????? #endif } #include "dma.h" u16 DMA1_MEM_LEN;//±￡′?DMA??′?êy?Y′??íμ?3¤?è //DMA1μ??÷í¨μà???? //?aà?μ?′?ê?D?ê?ê?1ì?¨μ?,?aμ?òa?ù?Y2?í?μ??é??à′DT?? //′ó′?′￠?÷->íaéè?￡ê?/8??êy?Y?í?è/′?′￠?÷??á??￡ê? //DMA_CHx:DMAí¨μàCHx //cpar:íaéèμ??· //cmar:′?′￠?÷μ??· //cndtr:êy?Y′?ê?á? void MYDMA_Config(DMA_Channel_TypeDef*DMA_CHx,u32 cpar,u32 cmar,u16 cndtr,bool dir) { RCC->AHBENR|=1<<0;//?a??DMA1ê±?ó __nop(); __nop(); __nop(); while(DMA_CHx->CCR&0X01) ; //1?±?DMA;//μè′yDMA?é???? DMA_CHx->CPAR=cpar; //DMA1 íaéèμ??· DMA_CHx->CMAR=(u32)cmar; //DMA1,′?′￠?÷μ??· DMA1_MEM_LEN=cndtr; //±￡′?DMA′?ê?êy?Yá? DMA_CHx->CNDTR=cndtr; //DMA1,′?ê?êy?Yá? DMA_CHx->CCR=0X00000000;//?′?? if(dir) DMA_CHx->CCR|=1<<4; //′ó′?′￠?÷?á else DMA_CHx->CCR&=0xffff-1<<4; DMA_CHx->CCR|=0<<5; //??í¨?￡ê? DMA_CHx->CCR|=0<<6; //íaéèμ??··???á??￡ê? DMA_CHx->CCR|=1<<7; //′?′￠?÷??á??￡ê? DMA_CHx->CCR|=0<<8; //íaéèêy?Y?í?è?a8?? DMA_CHx->CCR|=0<<10; //′?′￠?÷êy?Y?í?è8?? DMA_CHx->CCR|=1<<12; //?Dμèó??è?? DMA_CHx->CCR|=0<<14; //·?′?′￠?÷μ?′?′￠?÷?￡ê? } //?a??ò?′?DMA′?ê? void MYDMA_Enable(DMA_Channel_TypeDef*DMA_CHx) { DMA_CHx->CCR&=~(1<<0); //1?±?DMA′?ê? DMA_CHx->CNDTR=DMA1_MEM_LEN; //DMA1,′?ê?êy?Yá? DMA_CHx->CCR|=1<<0; //?a??DMA′?ê? } 主程序如下 #include <stm32f10x_lib.h> #include "sys.h" #include "usart.h" #include "delay.h" #include "led.h" #include "key.h" #include "exti.h" #include "wdg.h" #include "timer.h" #include "lcd.h" #include "rtc.h" #include "wkup.h" #include "adc.h" #include "dma.h" #include "ds18b20.h" extern u8 dmabuffer[8]; int main(void) { u16 j=0; u16 i; short temp; Stm32_Clock_Init(6);//?μí3ê±?óéè?? delay_init(72); //?óê±3?ê??ˉ uart1_init(72,9600); //′??ú13?ê??ˉ uart3_init(36,115200); //′??ú33?ê??ˉ RCC->APB2ENR|=1<<4; //ê1?üPORTCê±?ó GPIOC->CRH&=0XFFF0FFFF; GPIOC->CRH|=0X00030000;//PC12 í?íìê?3? MYDMA_Config(DMA1_Channel2,(u32)&USART3->DR,(u32)dmabuffer,8,1); MYDMA_Config(DMA1_Channel3,(u32)&USART3->DR,(u32)dmabuffer,8,0); while(1) { temp=DS18B20_Get_Temp(); if(temp) printf("%d ",temp); LED0=!LED0;//ìáê??μí3?y?ú??DD } } |
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