基于STM32 Modbus rtu 从机代码 开源 （附上测试工程）-------------------------2代码风格（偏通用移植）

Modbus rtu 从机代码主要包括五组：

modbus.c   modbus.h    
modbus_485.c  modbus_485.h  
modbus_crc.c   modbus_crc.h
modbus_time.c   modbus_time.h
modbus_uart.c   modbus_uart.h

#include "modbus.h"
MODBUS modbus;
u16 Reg[] ={0x0001,
            0x0002,
            0x0003,
            0x0004,
	          0x0005,
            0x0006,
            0x0007,
           };
// Modbus初始化函数
void Modbus_Init()
{
  modbus.myadd = 0x01; //从机设备地址为1
  modbus.timrun = 0;    //modbus定时器停止计算
	Modbus_485_Init();
	Modbus_Uart_Init();
	Modbus_Time_Init();
}

// Modbus 3号功能码函数
// Modbus 主机读取寄存器值
void Modbus_Func3()
{
  u16 Regadd,Reglen,crc;
	u8 i,j;	
	//得到要读取寄存器的首地址
	Regadd = modbus.rcbuf[2]*256+modbus.rcbuf[3];
	//得到要读取寄存器的数据长度
	Reglen = modbus.rcbuf[4]*256+modbus.rcbuf[5];
	//发送回应数据包
	i = 0;
	modbus.sendbuf[i++] = modbus.myadd;      //发送本机设备地址
	modbus.sendbuf[i++] = 0x03;              //发送功能码
  modbus.sendbuf[i++] = ((Reglen*2)%256);   //返回字节个数
	for(j=0;j

#ifndef _modbus_h_
#define _modbus_h_
#include "stm32f10x.h"
#include "modbus_crc.h"
#include "modbus_uart.h"
#include "modbus_485.h"
#include "modbus_time.h"


typedef struct 
{
  u8  myadd;        //本设备从机地址
	u8  rcbuf[100];   //modbus接受缓冲区
	u8  timout;       //modbus数据持续时间
	u8  recount;      //modbus端口接收到的数据个数
	u8  timrun;       //modbus定时器是否计时标志
	u8  reflag;       //modbus一帧数据接受完成标志位
	u8  sendbuf[100]; //modbus接发送缓冲区
	
}MODBUS;

extern MODBUS modbus;
extern u16 Reg[];
void Modbus_Init(void);
void Modbus_Func3(void);
void Modbus_Event(void);
void ISR_Init(void);

#endif

#include "modbus_485.h"

void Modbus_485_Init()
{
 //Modbus_485_RT GPIO端口设置
 GPIO_InitTypeDef GPIO_InitStructure;
 RCC_APB2PeriphClockCmd(Modbus_485_RT_Clock, ENABLE);	//使能485_RT时钟
	
 GPIO_InitStructure.GPIO_Pin = Modbus_485_RT_Pin;			//485_RT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(Modbus_485_RT_Port, &GPIO_InitStructure);	//根据设定参数初始化
 Modbus_485_RX_Mode; //初始化为接收状态
}

#ifndef _modbus_485_h_
#define _modbus_485_h_
#include "stm32f10x.h"

// modbus信号控制端口 
#define Modbus_485_RT_Port    GPIOC
#define Modbus_485_RT_Pin     GPIO_Pin_2
#define Modbus_485_RT_Clock   RCC_APB2Periph_GPIOC

#define Modbus_485_RX_Mode    GPIO_ResetBits(Modbus_485_RT_Port,Modbus_485_RT_Pin)
#define Modbus_485_TX_Mode    GPIO_SetBits(Modbus_485_RT_Port,Modbus_485_RT_Pin)

void Modbus_485_Init(void);

#endif

#include "modbus_crc.h"

/* CRC 高位字节值表 */
const u8 auchCRCHi[] = {
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
    0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
    0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
    0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
    0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
    0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
    0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
    0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
    0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
    0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
    0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40,
    0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1,
    0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
    0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0,
    0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
} ;
/* CRC低位字节值表*/
const u8 auchCRCLo[] = {
    0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06,
    0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04, 0xCC, 0x0C, 0x0D, 0xCD,
    0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09,
    0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A,
    0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC, 0x14, 0xD4,
    0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3,
    0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3,
    0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4,
    0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A,
    0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29,
    0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED,
    0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
    0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60,
    0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67,
    0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F,
    0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68,
    0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E,
    0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5,
    0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71,
    0x70, 0xB0, 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92,
    0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C,
    0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B,
    0x99, 0x59, 0x58, 0x98, 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B,
    0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
    0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42,
    0x43, 0x83, 0x41, 0x81, 0x80, 0x40
} ;


/******************************************************************
功能: CRC16校验
输入:
输出:
******************************************************************/
u16  Modbus_CRC16( u8 *puchMsg, u16 usDataLen )
{
    u8 uchCRCHi = 0xFF ; // 高CRC字节初始化
    u8 uchCRCLo = 0xFF ; // 低CRC 字节初始化
    unsigned long uIndex ; 		// CRC循环中的索引

    while ( usDataLen-- ) 	// 传输消息缓冲区
    {
        uIndex = uchCRCHi ^ *puchMsg++ ; 	// 计算CRC
        uchCRCHi = uchCRCLo ^ auchCRCHi[uIndex] ;
        uchCRCLo = auchCRCLo[uIndex] ;
    }

    return ( uchCRCHi << 8 | uchCRCLo ) ;
}

#ifndef _modbus_crc_h_
#define _modbus_crc_h_
#include "stm32f10x.h"




u16  Modbus_CRC16( u8 *puchMsg, u16 usDataLen );


#endif

#include "modbus_time.h"

void Modbus_Time_Init()
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	RCC_APB1PeriphClockCmd(Modbus_Time_Clock, ENABLE); //TIM时钟使能

	TIM_TimeBaseStructure.TIM_Period = Modbus_Time_arr;    //自动重装载寄存器周期的值	 
	TIM_TimeBaseStructure.TIM_Prescaler =Modbus_Time_psc; //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;  //TIM向上计数模式
	TIM_TimeBaseInit(Modbus_Timer, &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(Modbus_Timer,TIM_IT_Update,ENABLE);  //使能或者失能指定的TIM中断
	TIM_Cmd(Modbus_Timer, ENABLE);  //使能TIMx外设
}

// Modbus 定时器中断函数 1ms中断一次
void Modbus_TIM_IRQHandler(void)  
{
	if (TIM_GetITStatus(Modbus_Timer, TIM_IT_Update) != RESET) //检查指定的TIM中断发生与否:TIM 中断源 
	{
		TIM_ClearITPendingBit(Modbus_Timer, TIM_IT_Update);  //清除TIMx的中断待处理位:TIM 中断源 
		if(modbus.timrun != 0)
		 {
		  modbus.timout++;
		  if(modbus.timout >=8)
		  {
		   modbus.timrun = 0;
			 modbus.reflag = 1;
		  }
		 }			
	}
}

#ifndef _modbus_time_h_
#define _modbus_time_h_
#include "stm32f10x.h"
#include "modbus.h"

/*************modbus默认定时器TIM3******************/
/*************可修改对应的宏来修改TIM****************/

#define Modbus_Time_arr               (1000-1) //1us*1000=1ms 
#define Modbus_Time_psc               (72-1)   //72M/72 =1us
#define Modbus_Time_Clock             RCC_APB1Periph_TIM3
#define Modbus_Timer                  TIM3
#define Modbus_Time_IRQn              TIM3_IRQn
#define Modbus_TIM_IRQHandler(void)   TIM3_IRQHandler(void)

void Modbus_Time_Init(void);
#endif 

#include "modbus_uart.h"

// Modbus串口初始化
void Modbus_Uart_Init()
{
  //GPIO端口设置
  GPIO_InitTypeDef GPIO_InitStructure;
	USART_InitTypeDef USART_InitStructure;
	RCC_APB1PeriphClockCmd(Modbus_Uart_Clock,ENABLE);       //使能Modbus串口时钟
	RCC_APB2PeriphClockCmd(Modbus_Uart_GPIO_Clock|RCC_APB2Periph_AFIO,ENABLE);	//使能Modbus串口GPIO时钟
  
	//Moubud USART_TX   
  GPIO_InitStructure.GPIO_Pin = Modbus_Uart_TX_Pin; 
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;	        //复用推挽输出
  GPIO_Init(Modbus_Uart_TRX_Port, &GPIO_InitStructure);   //初始化 
  //Moubud USART_RX
  GPIO_InitStructure.GPIO_Pin = Modbus_Uart_RX_Pin;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;    //浮空输入
  GPIO_Init(Modbus_Uart_TRX_Port, &GPIO_InitStructure);    //初始化 
  
  //Moubud USART 初始化设置
	USART_InitStructure.USART_BaudRate = Modbus_bound;//串口波特率
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式
	USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位
	USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制
	USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;	//收发模式
  USART_Init(Modbus_USART, &USART_InitStructure);     //初始化Moubud USART
  USART_ITConfig(Modbus_USART, USART_IT_RXNE, ENABLE);//开启串口接受中断
  USART_Cmd(Modbus_USART, ENABLE);                    //使能Moubud USART
}

//modbus串口发送一个字节数据
void Modbus_Send_Byte(u8 Modbus_byte)
{
  USART_SendData(Modbus_USART,Modbus_byte);
	while(USART_GetFlagStatus(Modbus_USART, USART_FLAG_TC) == RESET);
	USART_ClearFlag(Modbus_USART, USART_FLAG_TC); 
}

//modbus串口中断服务程序
void Modbus_USART_IRQHandler(void)                
{
  u8 st,Res;
	st = USART_GetITStatus(Modbus_USART, USART_IT_RXNE);
	if(st == SET)//接收中断
	{
		Res =USART_ReceiveData(Modbus_USART);	//读取接收到的数据
	  
	 if( modbus.reflag==1)  //有数据包正在处理
	  {
		   return ;
		}		
	  modbus.rcbuf[modbus.recount++] = Res;
		modbus.timout = 0;
		if(modbus.recount == 1)  //已经收到了第二个字符数据
		{
		  modbus.timrun = 1;  //开启modbus定时器计时
		}
	}	
} 

#ifndef _modbus_uart_h_
#define _modbus_uart_h_

#include "stm32f10x.h"
#include "modbus.h"

#define Modbus_bound             9600
#define Modbus_USART             USART2
#define Modbus_Uart_Clock        RCC_APB1Periph_USART2
#define Modbus_Uart_GPIO_Clock   RCC_APB2Periph_GPIOA
#define Modbus_Uart_TRX_Port     GPIOA      
#define Modbus_Uart_TX_Pin       GPIO_Pin_2
#define Modbus_Uart_RX_Pin       GPIO_Pin_3

#define Modbus_USART_IRQn              USART2_IRQn
#define Modbus_USART_IRQHandler(void)  USART2_IRQHandler(void) 

void Modbus_Uart_Init(void);
void Modbus_Send_Byte(u8 Modbus_byte);

#endif