一、IIC的定义
I2C总线是双向、baidu两线(SCL、SDA)、串行、多主控zhi(multi-master)接口标准,具有总线dao仲裁机制,非zhuan常适合在器件之间进行近shu距离、非经常性的数据通信。在它的协议体系中,传输数据时都会带上目的设备的设备地址,因此可以实现设备组网。如果用通用IO口模拟I2C总线,并实现双向传输,则需一个输入输出口(SDA),另外还需一个输出口(SCL)。
二、stm32f103指南者外接AHT20进行温湿度采集
1.硬件连接
把AHT20的SCL,GND,SDA,VCC分别连接到stm32开发板I²C模块的B6,GND,B7,5V。
2.代码编写
1)打开野火官方固件库中的BH-F103工程文件
2)在USER文件夹中添加以下代码
在main.c中
#include "delay.h"
#include "usart.h"
#include "bsp_i2c.h"
int main(void)
{
delay_init(); //ÑÓʱº¯Êý³õʼ»¯
uart_init(115200); //´®¿Ú³õʼ»¯Îª115200
IIC_Init();
while(1)
{
read_AHT20_once();
delay_ms(1500);
}
}
在usart.c中
#include "sys.h"
#include "usart.h"
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//Èç¹ûʹÓÃucos,Ôò°üÀ¨ÏÂÃæµÄÍ·Îļþ¼´¿É.
#if SYSTEM_SUPPORT_UCOS
#include "includes.h" //ucos ʹÓÃ
#endif
//
//STM32¿ª·¢°å
//´®¿Ú1³õʼ»¯
//
//
//¼ÓÈëÒÔÏ´úÂë,Ö§³Öprintfº¯Êý,¶ø²»ÐèҪѡÔñuse MicroLIB
#if 1
#pragma import(__use_no_semihosting)
//±ê×¼¿âÐèÒªµÄÖ§³Öº¯Êý
struct __FILE
{
int handle;
};
FILE __stdout;
//¶¨Òå_sys_exit()ÒÔ±ÜÃâʹÓðëÖ÷»úģʽ
void _sys_exit(int x)
{
x = x;
}
//ÖØ¶¨Òåfputcº¯Êý
int fputc(int ch, FILE *f)
{
while((USART1->SR&0X40)==0);//Ñ»··¢ËÍ,Ö±µ½·¢ËÍÍê±Ï
USART1->DR = (u8) ch;
return ch;
}
#endif
/*ʹÓÃmicroLibµÄ·½·¨*/
/*
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 //Èç¹ûʹÄÜÁ˽ÓÊÕ
//´®¿Ú1ÖжϷþÎñ³ÌÐò
//×¢Òâ,¶ÁÈ¡USARTx->SRÄܱÜÃâĪÃûÆäÃîµÄ´íÎó
u8 USART_RX_BUF[USART_REC_LEN]; //½ÓÊÕ»º³å,×î´óUSART_REC_LEN¸ö×Ö½Ú.
//½ÓÊÕ״̬
//bit15£¬ ½ÓÊÕÍê³É±êÖ¾
//bit14£¬ ½ÓÊÕµ½0x0d
//bit13~0£¬ ½ÓÊÕµ½µÄÓÐЧ×Ö½ÚÊýÄ¿
u16 USART_RX_STA=0; //½ÓÊÕ״̬±ê¼Ç
void uart_init(u32 bound){
//GPIO¶Ë¿ÚÉèÖÃ
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //ʹÄÜUSART1£¬GPIOAʱÖÓ
//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; //¸´ÓÃÍÆÍìÊä³ö
GPIO_Init(GPIOA, &GPIO_InitStructure);
//USART1_RX PA.10
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//¸¡¿ÕÊäÈë
GPIO_Init(GPIOA, &GPIO_InitStructure);
//Usart1 NVIC ÅäÖÃ
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//ÇÀÕ¼ÓÅÏȼ¶3
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //×ÓÓÅÏȼ¶3
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQͨµÀʹÄÜ
NVIC_Init(&NVIC_InitStructure); //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õʼ»¯VIC¼Ä´æÆ÷
//USART ³õʼ»¯ÉèÖÃ
USART_InitStructure.USART_BaudRate = bound;//Ò»°ãÉèÖÃΪ9600;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//×Ö³¤Îª8λÊý¾Ý¸ñʽ
USART_InitStructure.USART_StopBits = USART_StopBits_1;//Ò»¸öֹͣλ
USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæÅ¼Ð£Ñéλ
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //ÊÕ·¢Ä£Ê½
USART_Init(USART1, &USART_InitStructure); //³õʼ»¯´®¿Ú
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//¿ªÆôÖжÏ
USART_Cmd(USART1, ENABLE); //ʹÄÜ´®¿Ú
}
void USART1_IRQHandler(void) //´®¿Ú1ÖжϷþÎñ³ÌÐò
{
u8 Res;
#ifdef OS_TICKS_PER_SEC //Èç¹ûʱÖÓ½ÚÅÄÊý¶¨ÒåÁË,˵Ã÷ҪʹÓÃucosIIÁË.
OSIntEnter();
#endif
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //½ÓÊÕÖжÏ(½ÓÊÕµ½µÄÊý¾Ý±ØÐëÊÇ0x0d 0x0a½áβ)
{
Res =USART_ReceiveData(USART1);//(USART1->DR); //¶ÁÈ¡½ÓÊÕµ½µÄÊý¾Ý
if((USART_RX_STA&0x8000)==0)//½ÓÊÕδÍê³É
{
if(USART_RX_STA&0x4000)//½ÓÊÕµ½ÁË0x0d
{
if(Res!=0x0a)USART_RX_STA=0;//½ÓÊÕ´íÎó,ÖØÐ¿ªÊ¼
else USART_RX_STA|=0x8000; //½ÓÊÕÍê³ÉÁË
}
else //»¹Ã»ÊÕµ½0X0D
{
if(Res==0x0d)USART_RX_STA|=0x4000;
else
{
USART_RX_BUF[USART_RX_STA&0X3FFF]=Res ;
USART_RX_STA++;
if(USART_RX_STA>(USART_REC_LEN-1))USART_RX_STA=0;//½ÓÊÕÊý¾Ý´íÎó,ÖØÐ¿ªÊ¼½ÓÊÕ
}
}
}
}
#ifdef OS_TICKS_PER_SEC //Èç¹ûʱÖÓ½ÚÅÄÊý¶¨ÒåÁË,˵Ã÷ҪʹÓÃucosIIÁË.
OSIntExit();
#endif
}
#endif
在usart.h中
#ifndef __USART_H
#define __USART_H
#include "stdio.h"
#include "sys.h"
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//STM32¿ª·¢°å
//´®¿Ú1³õʼ»¯
#define USART_REC_LEN 200 //¶¨Òå×î´ó½ÓÊÕ×Ö½ÚÊý 200
#define EN_USART1_RX 1 //ʹÄÜ£¨1£©/½ûÖ¹£¨0£©´®¿Ú1½ÓÊÕ
extern u8 USART_RX_BUF[USART_REC_LEN]; //½ÓÊÕ»º³å,×î´óUSART_REC_LEN¸ö×Ö½Ú.Ä©×Ö½ÚΪ»»Ðзû
extern u16 USART_RX_STA; //½ÓÊÕ״̬±ê¼Ç
//Èç¹ûÏë´®¿ÚÖжϽÓÊÕ£¬Ç벻ҪעÊÍÒÔϺ궨Òå
void uart_init(u32 bound);
#endif
在bsp_i2c.c中
#include "delay.h"
#include "sys.h"
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//Èç¹ûʹÓÃucos,Ôò°üÀ¨ÏÂÃæµÄÍ·Îļþ¼´¿É.
#if SYSTEM_SUPPORT_UCOS
#include "includes.h" //ucos ʹÓÃ
#endif
//
//STM32¿ª·¢°å
//ʹÓÃSysTickµÄÆÕͨ¼ÆÊýģʽ¶ÔÑÓ³Ù½øÐйÜÀí
//°üÀ¨delay_us,delay_ms
//
static u8 fac_us=0;//usÑÓʱ±¶³ËÊý
static u16 fac_ms=0;//msÑÓʱ±¶³ËÊý
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
//systickÖжϷþÎñº¯Êý,ʹÓÃucosʱÓõ½
void SysTick_Handler(void)
{
OSIntEnter(); //½øÈëÖжÏ
OSTimeTick(); //µ÷ÓÃucosµÄʱÖÓ·þÎñ³ÌÐò
OSIntExit(); //´¥·¢ÈÎÎñÇл»ÈíÖжÏ
}
#endif
//³õʼ»¯ÑÓ³Ùº¯Êý
//µ±Ê¹ÓÃucosµÄʱºò,´Ëº¯Êý»á³õʼ»¯ucosµÄʱÖÓ½ÚÅÄ
//SYSTICKµÄʱÖӹ̶¨ÎªHCLKʱÖÓµÄ1/8
//SYSCLK:ϵͳʱÖÓ
void delay_init()
{
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
u32 reload;
#endif
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK_Div8); //Ñ¡ÔñÍⲿʱÖÓ HCLK/8
fac_us=SystemCoreClock/8000000; //ΪϵͳʱÖÓµÄ1/8
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
reload=SystemCoreClock/8000000; //ÿÃëÖӵļÆÊý´ÎÊý µ¥Î»ÎªK
reload*=1000000/OS_TICKS_PER_SEC;//¸ù¾ÝOS_TICKS_PER_SECÉ趨Òç³öʱ¼ä
//reloadΪ24λ¼Ä´æÆ÷,×î´óÖµ:16777216,ÔÚ72MÏÂ,Ô¼ºÏ1.86s×óÓÒ
fac_ms=1000/OS_TICKS_PER_SEC;//´ú±íucos¿ÉÒÔÑÓʱµÄ×îÉÙµ¥Î»
SysTick->CTRL|=SysTick_CTRL_TICKINT_Msk; //¿ªÆôSYSTICKÖжÏ
SysTick->LOAD=reload; //ÿ1/OS_TICKS_PER_SECÃëÖжÏÒ»´Î
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk; //¿ªÆôSYSTICK
#else
fac_ms=(u16)fac_us*1000;//·ÇucosÏÂ,´ú±íÿ¸ömsÐèÒªµÄsystickʱÖÓÊý
#endif
}
#ifdef OS_CRITICAL_METHOD //ʹÓÃÁËucos
//ÑÓʱnus
//nusΪҪÑÓʱµÄusÊý.
void delay_us(u32 nus)
{
u32 ticks;
u32 told,tnow,tcnt=0;
u32 reload=SysTick->LOAD; //LOADµÄÖµ
ticks=nus*fac_us; //ÐèÒªµÄ½ÚÅÄÊý
tcnt=0;
told=SysTick->VAL; //¸Õ½øÈëʱµÄ¼ÆÊýÆ÷Öµ
while(1)
{
tnow=SysTick->VAL;
if(tnow!=told)
{
if(tnow<told)tcnt+=told-tnow;//ÕâÀï×¢ÒâÒ»ÏÂSYSTICKÊÇÒ»¸öµÝ¼õµÄ¼ÆÊýÆ÷¾Í¿ÉÒÔÁË.
else tcnt+=reload-tnow+told;
told=tnow;
if(tcnt>=ticks)break;//ʱ¼ä³¬¹ý/µÈÓÚÒªÑÓ³ÙµÄʱ¼ä,ÔòÍ˳ö.
}
};
}
//ÑÓʱnms
//nms:ÒªÑÓʱµÄmsÊý
void delay_ms(u16 nms)
{
if(OSRunning==TRUE)//Èç¹ûosÒѾÔÚÅÜÁË
{
if(nms>=fac_ms)//ÑÓʱµÄʱ¼ä´óÓÚucosµÄ×îÉÙʱ¼äÖÜÆÚ
{
OSTimeDly(nms/fac_ms);//ucosÑÓʱ
}
nms%=fac_ms; //ucosÒѾÎÞ·¨ÌṩÕâôСµÄÑÓʱÁË,²ÉÓÃÆÕͨ·½Ê½ÑÓʱ
}
delay_us((u32)(nms*1000)); //ÆÕͨ·½Ê½ÑÓʱ,´ËʱucosÎÞ·¨Æô¶¯µ÷¶È.
}
#else//²»ÓÃucosʱ
//ÑÓʱnus
//nusΪҪÑÓʱµÄusÊý.
void delay_us(u32 nus)
{
u32 temp;
SysTick->LOAD=nus*fac_us; //ʱ¼ä¼ÓÔØ
SysTick->VAL=0x00; //Çå¿Õ¼ÆÊýÆ÷
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ; //¿ªÊ¼µ¹Êý
do
{
temp=SysTick->CTRL;
}
while(temp&0x01&&!(temp&(1<<16)));//µÈ´ýʱ¼äµ½´ï
SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk; //¹Ø±Õ¼ÆÊýÆ÷
SysTick->VAL =0X00; //Çå¿Õ¼ÆÊýÆ÷
}
//ÑÓʱnms
//×¢ÒânmsµÄ·¶Î§
//SysTick->LOADΪ24λ¼Ä´æÆ÷,ËùÒÔ,×î´óÑÓʱΪ:
//nms<=0xffffff*8*1000/SYSCLK
//SYSCLKµ¥Î»ÎªHz,nmsµ¥Î»Îªms
//¶Ô72MÌõ¼þÏÂ,nms<=1864
void delay_ms(u16 nms)
{
u32 temp;
SysTick->LOAD=(u32)nms*fac_ms;//ʱ¼ä¼ÓÔØ(SysTick->LOADΪ24bit)
SysTick->VAL =0x00; //Çå¿Õ¼ÆÊýÆ÷
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ; //¿ªÊ¼µ¹Êý
do
{
temp=SysTick->CTRL;
}
while(temp&0x01&&!(temp&(1<<16)));//µÈ´ýʱ¼äµ½´ï
SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk; //¹Ø±Õ¼ÆÊýÆ÷
SysTick->VAL =0X00; //Çå¿Õ¼ÆÊýÆ÷
}
#endif
在bsp_i2c.h中
#ifndef __BSP_I2C_H
#define __BSP_I2C_H
#include "sys.h"
#include "delay.h"
#include "usart.h"
//ʹÓÃIIC1 ¹ÒÔØM24C02,OLED,LM75AD,HT1382 PB6,PB7
#define SDA_IN() {GPIOB->CRL&=0X0FFFFFFF;GPIOB->CRL|=(u32)8<<28;}
#define SDA_OUT() {GPIOB->CRL&=0X0FFFFFFF;GPIOB->CRL|=(u32)3<<28;}
//IO²Ù×÷º¯Êý
#define IIC_SCL PBout(6) //SCL
#define IIC_SDA PBout(7) //SDA
#define READ_SDA PBin(7) //ÊäÈëSDA
//IICËùÓвÙ×÷º¯Êý
void IIC_Init(void); //³õʼ»¯IICµÄIO¿Ú
void IIC_Start(void); //·¢ËÍIIC¿ªÊ¼ÐźÅ
void IIC_Stop(void); //·¢ËÍIICÍ£Ö¹ÐźÅ
void IIC_Send_Byte(u8 txd); //IIC·¢ËÍÒ»¸ö×Ö½Ú
u8 IIC_Read_Byte(unsigned char ack);//IIC¶Áȡһ¸ö×Ö½Ú
u8 IIC_Wait_Ack(void); //IICµÈ´ýACKÐźÅ
void IIC_Ack(void); //IIC·¢ËÍACKÐźÅ
void IIC_NAck(void); //IIC²»·¢ËÍACKÐźÅ
void IIC_WriteByte(uint16_t addr,uint8_t data,uint8_t device_addr);
uint16_t IIC_ReadByte(uint16_t addr,uint8_t device_addr,uint8_t ByteNumToRead);//¼Ä´æÆ÷µØÖ·£¬Æ÷¼þµØÖ·£¬Òª¶ÁµÄ×Ö½ÚÊý
void read_AHT20_once(void);
void reset_AHT20(void);
void init_AHT20(void);
void startMeasure_AHT20(void);
void read_AHT20(void);
uint8_t Receive_ACK(void);
void Send_ACK(void);
void SendNot_Ack(void);
void I2C_WriteByte(uint8_t input);
uint8_t I2C_ReadByte(void);
void set_AHT20sendOutData(void);
void I2C_Start(void);
void I2C_Stop(void);
#endif
在delay.c中
#include "delay.h"
#include "sys.h"
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//Èç¹ûʹÓÃucos,Ôò°üÀ¨ÏÂÃæµÄÍ·Îļþ¼´¿É.
#if SYSTEM_SUPPORT_UCOS
#include "includes.h" //ucos ʹÓÃ
#endif
//
//STM32¿ª·¢°å
//ʹÓÃSysTickµÄÆÕͨ¼ÆÊýģʽ¶ÔÑÓ³Ù½øÐйÜÀí
//°üÀ¨delay_us,delay_ms
//
static u8 fac_us=0;//usÑÓʱ±¶³ËÊý
static u16 fac_ms=0;//msÑÓʱ±¶³ËÊý
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
//systickÖжϷþÎñº¯Êý,ʹÓÃucosʱÓõ½
void SysTick_Handler(void)
{
OSIntEnter(); //½øÈëÖжÏ
OSTimeTick(); //µ÷ÓÃucosµÄʱÖÓ·þÎñ³ÌÐò
OSIntExit(); //´¥·¢ÈÎÎñÇл»ÈíÖжÏ
}
#endif
//³õʼ»¯ÑÓ³Ùº¯Êý
//µ±Ê¹ÓÃucosµÄʱºò,´Ëº¯Êý»á³õʼ»¯ucosµÄʱÖÓ½ÚÅÄ
//SYSTICKµÄʱÖӹ̶¨ÎªHCLKʱÖÓµÄ1/8
//SYSCLK:ϵͳʱÖÓ
void delay_init()
{
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
u32 reload;
#endif
SysTick_CLKSourceConfig(SysTick_CLKSource_HCLK_Div8); //Ñ¡ÔñÍⲿʱÖÓ HCLK/8
fac_us=SystemCoreClock/8000000; //ΪϵͳʱÖÓµÄ1/8
#ifdef OS_CRITICAL_METHOD //Èç¹ûOS_CRITICAL_METHOD¶¨ÒåÁË,˵Ã÷ʹÓÃucosIIÁË.
reload=SystemCoreClock/8000000; //ÿÃëÖӵļÆÊý´ÎÊý µ¥Î»ÎªK
reload*=1000000/OS_TICKS_PER_SEC;//¸ù¾ÝOS_TICKS_PER_SECÉ趨Òç³öʱ¼ä
//reloadΪ24λ¼Ä´æÆ÷,×î´óÖµ:16777216,ÔÚ72MÏÂ,Ô¼ºÏ1.86s×óÓÒ
fac_ms=1000/OS_TICKS_PER_SEC;//´ú±íucos¿ÉÒÔÑÓʱµÄ×îÉÙµ¥Î»
SysTick->CTRL|=SysTick_CTRL_TICKINT_Msk; //¿ªÆôSYSTICKÖжÏ
SysTick->LOAD=reload; //ÿ1/OS_TICKS_PER_SECÃëÖжÏÒ»´Î
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk; //¿ªÆôSYSTICK
#else
fac_ms=(u16)fac_us*1000;//·ÇucosÏÂ,´ú±íÿ¸ömsÐèÒªµÄsystickʱÖÓÊý
#endif
}
#ifdef OS_CRITICAL_METHOD //ʹÓÃÁËucos
//ÑÓʱnus
//nusΪҪÑÓʱµÄusÊý.
void delay_us(u32 nus)
{
u32 ticks;
u32 told,tnow,tcnt=0;
u32 reload=SysTick->LOAD; //LOADµÄÖµ
ticks=nus*fac_us; //ÐèÒªµÄ½ÚÅÄÊý
tcnt=0;
told=SysTick->VAL; //¸Õ½øÈëʱµÄ¼ÆÊýÆ÷Öµ
while(1)
{
tnow=SysTick->VAL;
if(tnow!=told)
{
if(tnow<told)tcnt+=told-tnow;//ÕâÀï×¢ÒâÒ»ÏÂSYSTICKÊÇÒ»¸öµÝ¼õµÄ¼ÆÊýÆ÷¾Í¿ÉÒÔÁË.
else tcnt+=reload-tnow+told;
told=tnow;
if(tcnt>=ticks)break;//ʱ¼ä³¬¹ý/µÈÓÚÒªÑÓ³ÙµÄʱ¼ä,ÔòÍ˳ö.
}
};
}
//ÑÓʱnms
//nms:ÒªÑÓʱµÄmsÊý
void delay_ms(u16 nms)
{
if(OSRunning==TRUE)//Èç¹ûosÒѾÔÚÅÜÁË
{
if(nms>=fac_ms)//ÑÓʱµÄʱ¼ä´óÓÚucosµÄ×îÉÙʱ¼äÖÜÆÚ
{
OSTimeDly(nms/fac_ms);//ucosÑÓʱ
}
nms%=fac_ms; //ucosÒѾÎÞ·¨ÌṩÕâôСµÄÑÓʱÁË,²ÉÓÃÆÕͨ·½Ê½ÑÓʱ
}
delay_us((u32)(nms*1000)); //ÆÕͨ·½Ê½ÑÓʱ,´ËʱucosÎÞ·¨Æô¶¯µ÷¶È.
}
#else//²»ÓÃucosʱ
//ÑÓʱnus
//nusΪҪÑÓʱµÄusÊý.
void delay_us(u32 nus)
{
u32 temp;
SysTick->LOAD=nus*fac_us; //ʱ¼ä¼ÓÔØ
SysTick->VAL=0x00; //Çå¿Õ¼ÆÊýÆ÷
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ; //¿ªÊ¼µ¹Êý
do
{
temp=SysTick->CTRL;
}
while(temp&0x01&&!(temp&(1<<16)));//µÈ´ýʱ¼äµ½´ï
SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk; //¹Ø±Õ¼ÆÊýÆ÷
SysTick->VAL =0X00; //Çå¿Õ¼ÆÊýÆ÷
}
//ÑÓʱnms
//×¢ÒânmsµÄ·¶Î§
//SysTick->LOADΪ24λ¼Ä´æÆ÷,ËùÒÔ,×î´óÑÓʱΪ:
//nms<=0xffffff*8*1000/SYSCLK
//SYSCLKµ¥Î»ÎªHz,nmsµ¥Î»Îªms
//¶Ô72MÌõ¼þÏÂ,nms<=1864
void delay_ms(u16 nms)
{
u32 temp;
SysTick->LOAD=(u32)nms*fac_ms;//ʱ¼ä¼ÓÔØ(SysTick->LOADΪ24bit)
SysTick->VAL =0x00; //Çå¿Õ¼ÆÊýÆ÷
SysTick->CTRL|=SysTick_CTRL_ENABLE_Msk ; //¿ªÊ¼µ¹Êý
do
{
temp=SysTick->CTRL;
}
while(temp&0x01&&!(temp&(1<<16)));//µÈ´ýʱ¼äµ½´ï
SysTick->CTRL&=~SysTick_CTRL_ENABLE_Msk; //¹Ø±Õ¼ÆÊýÆ÷
SysTick->VAL =0X00; //Çå¿Õ¼ÆÊýÆ÷
}
#endif
在delay.h中
#ifndef __DELAY_H
#define __DELAY_H
#include "sys.h"
//
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//ʹÓÃSysTickµÄÆÕͨ¼ÆÊýģʽ¶ÔÑÓ³Ù½øÐйÜÀí
//°üÀ¨delay_us,delay_ms
//
void delay_init(void);
void delay_ms(u16 nms);
void delay_us(u32 nus);
#endif
在sys.c中
#include "sys.h"
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//STM32¿ª·¢°å
//ϵͳÖжϷÖ×éÉèÖû¯
//********************************************************************************
void NVIC_Configuration(void)
{
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //ÉèÖÃNVICÖжϷÖ×é2:2λÇÀÕ¼ÓÅÏȼ¶£¬2λÏìÓ¦ÓÅÏȼ¶
}
在sys.h
#ifndef __SYS_H
#define __SYS_H
#include "stm32f10x.h"
//
//STM32F103ºËÐİåÀý³Ì
//¿âº¯Êý°æ±¾Àý³Ì
/********** mcudev.taobao.com ³öÆ· ********/
//
//0,²»Ö§³Öucos
//1,Ö§³Öucos
#define SYSTEM_SUPPORT_UCOS 0 //¶¨ÒåϵͳÎļþ¼ÐÊÇ·ñÖ§³ÖUCOS
//λ´ø²Ù×÷,ʵÏÖ51ÀàËÆµÄGPIO¿ØÖƹ¦ÄÜ
//¾ßÌåʵÏÖ˼Ïë,²Î¿¼<<CM3ȨÍþÖ¸ÄÏ>>µÚÎåÕÂ(87Ò³~92Ò³).
//IO¿Ú²Ù×÷ºê¶¨Òå
#define BITBAND(addr, bitnum) ((addr & 0xF0000000)+0x2000000+((addr &0xFFFFF)<<5)+(bitnum<<2))
#define MEM_ADDR(addr) *((volatile unsigned long *)(addr))
#define BIT_ADDR(addr, bitnum) MEM_ADDR(BITBAND(addr, bitnum))
//IO¿ÚµØÖ·Ó³Éä
#define GPIOA_ODR_Addr (GPIOA_BASE+12) //0x4001080C
#define GPIOB_ODR_Addr (GPIOB_BASE+12) //0x40010C0C
#define GPIOC_ODR_Addr (GPIOC_BASE+12) //0x4001100C
#define GPIOD_ODR_Addr (GPIOD_BASE+12) //0x4001140C
#define GPIOE_ODR_Addr (GPIOE_BASE+12) //0x4001180C
#define GPIOF_ODR_Addr (GPIOF_BASE+12) //0x40011A0C
#define GPIOG_ODR_Addr (GPIOG_BASE+12) //0x40011E0C
#define GPIOA_IDR_Addr (GPIOA_BASE+8) //0x40010808
#define GPIOB_IDR_Addr (GPIOB_BASE+8) //0x40010C08
#define GPIOC_IDR_Addr (GPIOC_BASE+8) //0x40011008
#define GPIOD_IDR_Addr (GPIOD_BASE+8) //0x40011408
#define GPIOE_IDR_Addr (GPIOE_BASE+8) //0x40011808
#define GPIOF_IDR_Addr (GPIOF_BASE+8) //0x40011A08
#define GPIOG_IDR_Addr (GPIOG_BASE+8) //0x40011E08
//IO¿Ú²Ù×÷,Ö»¶Ôµ¥Ò»µÄIO¿Ú!
//È·±£nµÄֵСÓÚ16!
#define PAout(n) BIT_ADDR(GPIOA_ODR_Addr,n) //Êä³ö
#define PAin(n) BIT_ADDR(GPIOA_IDR_Addr,n) //ÊäÈë
#define PBout(n) BIT_ADDR(GPIOB_ODR_Addr,n) //Êä³ö
#define PBin(n) BIT_ADDR(GPIOB_IDR_Addr,n) //ÊäÈë
#define PCout(n) BIT_ADDR(GPIOC_ODR_Addr,n) //Êä³ö
#define PCin(n) BIT_ADDR(GPIOC_IDR_Addr,n) //ÊäÈë
#define PDout(n) BIT_ADDR(GPIOD_ODR_Addr,n) //Êä³ö
#define PDin(n) BIT_ADDR(GPIOD_IDR_Addr,n) //ÊäÈë
#define PEout(n) BIT_ADDR(GPIOE_ODR_Addr,n) //Êä³ö
#define PEin(n) BIT_ADDR(GPIOE_IDR_Addr,n) //ÊäÈë
#define PFout(n) BIT_ADDR(GPIOF_ODR_Addr,n) //Êä³ö
#define PFin(n) BIT_ADDR(GPIOF_IDR_Addr,n) //ÊäÈë
#define PGout(n) BIT_ADDR(GPIOG_ODR_Addr,n) //Êä³ö
#define PGin(n) BIT_ADDR(GPIOG_IDR_Addr,n) //ÊäÈë
void NVIC_Configuration(void);
#endif
3)编译代码,生成HEX文件
烧录程序到stm32中
观察现象
打开多功能调试助手,打开串口可看见以下现象。对AHT20模块吹气可看见湿度发生明显变化。