modbus.c

#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
//#include <avr/wdt.h>


#define SYNC 0x40
#define PARITY_EVEN 0x20
#define PARITY_ODD 0x30
#define STOP_2 0x04
#define DATA_5 0x00
#define DATA_6 0x02
#define DATA_7 0x04
#define DATA_8 0x06 //最高位置1,UMSELn设为0工作于异步模式
#define DATA_9 0x0c

#define FRAMING_ERROR (1<<FE)
#define PARITY_ERROR (1<<UPE)
#define DATA_OVERRUN (1<<DOR)
#define DATA_REGISTER_EMPTY (1<<UDRE)
#define RX_COMPLETE (1<<RXC)

#define SYSTEM_CLOCK 16000000L
#define BAUD_RATE 38400L//57600L测试通过

#define UART_RX_BUFFER_SIZE 1024
#define UART_RX_BUFFER_MASK (UART_RX_BUFFER_SIZE-1)
#if (UART_RX_BUFFER_SIZE & UART_RX_BUFFER_MASK)
#error RX buffer size is not a power of 2
#endif

#define UART_TX_BUFFER_SIZE 512
#define UART_TX_BUFFER_MASK (UART_TX_BUFFER_SIZE-1)//UART_RX_BUFFER_SIZE 128
#if (UART_TX_BUFFER_SIZE & UART_TX_BUFFER_MASK)
#error TX buffer size is not a power of 2
#endif

volatile static unsigned char UART_RxBuf[UART_RX_BUFFER_SIZE];//UART_RX_BUFFER_SIZE 128
volatile static unsigned char UART_RxHead;
volatile static unsigned char UART_RxTail;

volatile static unsigned char UART_TxBuf[UART_TX_BUFFER_SIZE];//UART_TX_BUFFER_SIZE 128
volatile static unsigned char UART_TxHead;
volatile static unsigned char UART_TxTail;

//volatile static 
unsigned char UART0_RxBuf[UART_RX_BUFFER_SIZE];//UART_RX_BUFFER_SIZE 128
volatile static unsigned char UART0_RxHead;
volatile static unsigned char UART0_RxTail;

volatile static unsigned int UART0_TxBuf[UART_TX_BUFFER_SIZE];//UART_TX_BUFFER_SIZE 128
volatile static unsigned char UART0_TxHead;
volatile static unsigned char UART0_TxTail;

//volatile static 
unsigned char UART1_RxBuf[UART_RX_BUFFER_SIZE];//UART_RX_BUFFER_SIZE 128
volatile static unsigned char UART1_RxHead;
volatile static unsigned char UART1_RxTail;

volatile static unsigned char UART1_TxBuf[UART_TX_BUFFER_SIZE];//UART_TX_BUFFER_SIZE 128
volatile static unsigned char UART1_TxHead;
volatile static unsigned char UART1_TxTail;

void Initialize(void);
void Serial_Initialize_UART0(unsigned long int baud);
void Serial_Initialize_UART1(unsigned long int baud);
void Timer0_Initialize(void);
void Timer3_Initialize(void);
unsigned char UART0_ReceiveByte(void);
void UART0_TransmitByte(unsigned char data);
unsigned char UART1_ReceiveByte(void);
void UART1_TransmitByte(unsigned char data);
void UART0_TransmitC(unsigned char c);
void UART0_TransmitString(unsigned char *ptr);
void UART1_TransmitC(unsigned char c);
void UART1_TransmitString(unsigned char *ptr);
void SendDataUp();
void SendDataDown(void);
extern unsigned char ReadTime(void);

unsigned char strCat(unsigned char *s1,unsigned char *s2);


void Initialize(void)
{
     //MCUCR=0x00;//PORTA,PORTC作普通口使用
	 Serial_Initialize_UART0(BAUD_RATE);
	 Serial_Initialize_UART1(BAUD_RATE);
	 //Timer0_Initialize();
	 Timer3_Initialize();
	 sei();	

}


void Serial_Initialize_UART0(unsigned long int baud)
{
	 unsigned short int ubrr0;
	 ubrr0=((SYSTEM_CLOCK/(16L*baud))-1);
	 UBRR0H=(unsigned char)(ubrr0>>8);//设置USART0波特率
	 UBRR0L=(unsigned char)ubrr0;
	 //UCSR0B=((1<<TXCIE0)|(1<<RXCIE0)|(1<<RXEN0)|(1<<TXEN0));//USART0接收结束中断使能,接收器发送器使能
	 UCSR0B=((1<<RXEN0)|(1<<TXEN0));	//初始化时先先进入定时中断,屏蔽接收发送中断,
	 UCSR0C=DATA_8; //异步,无奇偶校验,1位停止位,8数据位
	 
	 UART0_RxTail=0;
	 UART0_RxHead=0;
	 UART0_TxTail=0;
	 UART0_TxHead=0;
}


void Serial_Initialize_UART1(unsigned long int baud)
{
	 unsigned short int ubrr1;
	 ubrr1=((SYSTEM_CLOCK/(16L*baud))-1);
	 UBRR1H=(unsigned char)(ubrr1>>8);//设置USART1波特率
	 UBRR1L=(unsigned char)ubrr1;
	 //UCSR1B=((1<<TXCIE1)|(1<<RXCIE1)|(1<<RXEN1)|(1<<TXEN1));//USART1接收结束中断使能,接收器发送器使能
	 UCSR1B=((1<<RXEN1)|(1<<TXEN1));//初始化时先不打开接收发送中断
	 UCSR1C=DATA_8; //异步,无奇偶校验,1位停止位,8数据位
	 
	 UART1_RxTail=0;
	 UART1_RxHead=0;
	 UART1_TxTail=0;
	 UART1_TxHead=0;
}


void Timer0_Initialize(void)
{
	cli();
	TCNT0=0x63;//((0xff-0x63)+1)*1024*(1/16M)=10ms
	TCCR0=0x07;//定时器0 预分频比1024
	TIMSK=0x01;//开定时器0中断

}


void Timer3_Initialize(void)
{
	TCCR3B = 0x00;  //stop timer 

	//0.1s  0xffff+1-(16M/1024)*0.1=63973.5--0xf9e5
	//0.2s--0xf3cb
	//0.3s--0xEDB0

	//TCNT3H=0xff;
	//TCNT3L=0x64;
	//TCCR3B=0x05;//1024预分频

	TCNT3H=0xf3;
	TCNT3L=0xcb;
	TCCR3B=0x04;//256预分频

	ETIMSK|= (1 << TOIE3);//定时器3溢出中断

}


//由于单片机要实现和DTU与modbus模块的同时通讯,采用双串口CPU,
//串口0中断处理与DTU的数据通讯,串口1中断处理与modbus数据采集模块的通讯,
//串口0中断设置为高优先级中断,每接收到或发送完一个字节都进入中断处理,处理完毕立即退出中断
//通讯波特率都为38400 b/s,一个起始位,一个停止位。



//时间冲突问题,硬件接受或发送一个字节的时间为1 ms左右,而软件接受或发送一个字节的时间仅几μs。
//同时通讯实际上是将CPU时间分成很小的时间片,假设较快的串口发送或接受一个字节的最长时间为TRbyteMax,则CPU最长时间片一般应小于TRbyteMax/2,当然在接受或发送完一帧数据之后的间隙,CPU时间片可以适当延长,作一些必要的数据处理。


 //数据冲突问题,2个串口通讯分别使用各自的接受发送数据缓冲区和控制变量,
 //以减少中断保护数据量和防止数据冲突。
 //当主程序、串口2中断处理程序和其他中断处理程序往存储器中写数据时,
 //需在尽量短的时间内关闭串口1中断,关闭中断时间应小于几百μs,
 //防止其他程序数据没有写完之前串口1读此数据。


//UART0接收完成中断
SIGNAL(SIG_UART0_RECV)
{
     unsigned char data;
	 unsigned char tmphead;
	 
	 data=UDR0;//read the received data
	 //calculate buffer index
	 tmphead=(UART0_RxHead+1)&UART_RX_BUFFER_MASK;//UART_RX_BUFFER_MASK 127
	 UART0_RxHead=tmphead;//store new index
	 
     if(tmphead==UART0_RxTail)
	 	 {
		 	//ERROR! Receive buffer overflow
	     }
	 UART0_RxBuf[tmphead]=data; //store received data in buffer
	 //if ((status & (FRAMING_ERROR | PARITY_ERROR | DATA_OVERRUN))==0)
}


void UART0_ReceiveData(void)
{  
	 unsigned char UART0_RxBuf[UART_RX_BUFFER_SIZE] = {0};

	 UCSR0B |= (1<<RXCIE0);
}


//UART1接收完成中断
SIGNAL(SIG_UART1_RECV)
{
     unsigned char data;
	 unsigned char tmphead;
	 
	 data=UDR1;/* read the received data */
	 //calculate buffer index
	 tmphead=(UART1_RxHead+1)&UART_RX_BUFFER_MASK;//UART_RX_BUFFER_MASK 127
	 UART1_RxHead=tmphead;//store new index
	 
     if(tmphead==UART1_RxTail)
	 	 {
		 	/* ERROR! Receive buffer overflow */
	     }
	 UART1_RxBuf[tmphead]=data; //store received data in buffer
}


//UART0数据寄存器空中断
SIGNAL(SIG_UART0_DATA)
{
     unsigned char tmptail;
	 
	 if(UART0_TxHead!=UART0_TxTail)//check if all data is transmitted
	 	{
			/* calculate buffer index */
	     	tmptail=(UART0_TxTail+1)&UART_TX_BUFFER_MASK;//UART_TX_BUFFER_SIZE 128
		 	UART0_TxTail=tmptail;//store new index
		 	UDR0=UART0_TxBuf[tmptail];//start transmition
		 }
	 else
	 	{
	     	UCSR0B&=~(1<<UDRIE);//disable UDRE interrupt
		 }
}


//UART1数据寄存器空中断
SIGNAL(SIG_UART1_DATA)
//SIGNAL(SIG_UART1_TRANS)
{
     unsigned char tmptail;
	 
	 if(UART1_TxHead!=UART1_TxTail)//check if all data is transmitted
	 	{
		/* calculate buffer index */
	     tmptail=(UART1_TxTail+1)&UART_TX_BUFFER_MASK;//UART_TX_BUFFER_SIZE 128
		 UART1_TxTail=tmptail;//store new index
		 UDR1=UART1_TxBuf[tmptail];//start transmition
		 }
	 else
	 	{
	     	UCSR1B&=~(1<<UDRIE);//disable UDRE interrupt
		 }
}


unsigned char timer0count=0;
void ReadHoldRegister(void);

SIGNAL(SIG_OVERFLOW0)
{	
	TIMSK=0x00;//关定时器0中断

	timer0count++;

	//DDRA  |=(1<<3);//测试能否进入溢出中断
	//PORTA |=(1<<3);
	//_delay_ms(3000);
	//PORTA &=~(1<<3);
	//_delay_ms(3000);
	
	ReadHoldRegister();

	if(timer0count==15)	//150ms
	{
		//sendcommand(3,0x03,0x01);//读输入寄存器,startAddr,RegNum
		TIMSK=0x01;//开定时器0中断
	}
}


SIGNAL(SIG_OVERFLOW3)
{
	ETIMSK=0x00;//关定时器3溢出中断
	//DDRA  |=(1<<3);//测试能否进入溢出中断
	//PORTA ^=(1<<3);
	ReadHoldRegister();

	ETIMSK|= (1 << TOIE3);//开定时器3溢出中断
}



//将两个字符串连接起来
unsigned char strCat(unsigned char *s1,unsigned char *s2)
{
	int i=0,j=0;
	while(s1[i]!='')
		i++;
	while(s2[j]!='')
		s1[i++]=s2[j++];
	s1[i]='';
	return *s1;
}

	 
unsigned char UART0_ReceiveByte(void)
{
     unsigned char tmptail;
	 while(UART0_RxHead==UART0_RxTail);//wait for incoming data
	 //caculate buffer index
	 tmptail=(UART0_RxTail+1)&UART_RX_BUFFER_MASK;//UART_RX_BUFFER_MASK 127
	 UART0_RxTail=tmptail;//store new index
	 return UART0_RxBuf[tmptail];//return data
}


unsigned char UART1_ReceiveByte(void)
{
     unsigned char tmptail;
	 while(UART1_RxHead==UART1_RxTail);//wait for incoming data
	 //caculate buffer index
	 tmptail=(UART1_RxTail+1)&UART_RX_BUFFER_MASK;//UART_RX_BUFFER_MASK 127
	 UART1_RxTail=tmptail;//store new index
	 return UART1_RxBuf[tmptail];//return data
}


//发送采用查询方式
//USART0发送字符
unsigned char UART0_Receive(void) 
{
	/* 等待接收数据*/
	while ( !(UCSR0A & (1<<RXC0)) )
		;
	/* 从缓冲器中获取并返回数据*/
	return UDR0;
}



void UART0_TransmitByte(unsigned char data)
{
     unsigned char tmphead;
	 //caculate buffer index
	 tmphead=(UART0_TxHead+1)&UART_TX_BUFFER_MASK;//UART_TX_BUFFER_SIZE 128
	 while(tmphead==UART0_TxTail);//wait for free space in buffer
	 
	 UART0_TxBuf[tmphead]=data;//store new data in buffer
	 UART0_TxHead=tmphead;//store new index
	 UCSR0B|=(1<<UDRIE);//enable UDRIE interrupt
}

void UART1_TransmitByte(unsigned char data)
{
     unsigned char tmphead;
	 //caculate buffer index
	 tmphead=(UART1_TxHead+1)&UART_TX_BUFFER_MASK;//UART_TX_BUFFER_SIZE 128
	 while(tmphead==UART1_TxTail);//wait for free space in buffer
	 
	 UART1_TxBuf[tmphead]=data;//store new data in buffer
	 UART1_TxHead=tmphead;//store new index
	 UCSR1B|=(1<<UDRIE);//enable UDRIE interrupt
}


//发送采用查询方式
//USART0发送字符
void UART0_Transmit_c(unsigned char c) 
{
 	while(!(UCSR0A & (1<<UDRE)));//wait for empty transmit buffer
 	UDR0=c;
}

	 
//USART1发送字符
void UART1_Transmit_c(unsigned char c) //发送采用查询方式
{
 	while(!(UCSR1A & (1<<UDRE)));//wait for empty transmit buffer
 	UDR1=c;
}


void UART0_Transmit_String(unsigned char *ptr)
{
 	while (*ptr)
 	{
  		UART0_TransmitByte(*ptr++);
 	}
 	UART0_Transmit_c(0x0D);//结尾发送回车
 	UART0_Transmit_c(0x0A);//结尾发送换行
}


//USART1发送字符串
void UART1_Transmit_String(unsigned char *ptr)
{
 	while (*ptr)
 	{
  		UART1_TransmitByte(*ptr++);
 	}
 	UART1_Transmit_c(0x0D);//结尾发送回车
 	UART1_Transmit_c(0x0A);//结尾发送换行
}



void UART0_Transmit_HEX(unsigned char *ptr, int nLen)
{
 	for(int i=0; i<nLen; i++)
 	{
  		UART0_Transmit_c(ptr[i]);
 	}
}


void UART1_Transmit_HEX(unsigned char *ptr, int nLen)
{
 	for(int i=1; i<nLen; i++)
 	{
  		UART1_Transmit_c(ptr[i]);
 	}
}


/*
void wdt_init(void)
{
	asm("wdr");			//clr wdt
	WDTCR=0x0F;			//enable wdt,clk = 2048,1.8S
}

void watchdog_on(void) 
{
	//看门狗计数清零 
	asm("WDR");	
		
 	//WDTCR=0x1F;  	//使能watchdog,并且,采用1024K分频,典型溢出时间5V时1S 
 	WDTCR = (1 << WDE)|(1 << WDP2) | (1 << WDP1) | (1 << WDP0); // 启动看门狗定时, 复位周期为1S
} 


void WDT_off(void)
{
	//WDT复位
	asm("wdr");

	//置位WDCE 和 WDE
	WDTCR = (1<<WDCE) | (1<<WDE);

	//关闭WDT
	WDTCR = 0x00;
}
*/


unsigned short crc16(unsigned char* puchMsg, unsigned char usDataLen);

//往服务器发送数据
void ReadHoldRegister(void)
{	
	/*	
	unsigned char data_up;

	unsigned char CompayID[]={"shanghailianxun "};

	unsigned char DeviceCode[]={"DeviceCode "};

	unsigned char TransmitTimeStamp[]={"TimeStamp "};

	unsigned char DDC_Name[]={"DDC_0001 "};

	unsigned char NV_Name[]={"NV_001 "};

	unsigned char State[]={"State "};

	unsigned char Space[]={" "};

	unsigned char NVF[]={"NVF "};

	unsigned char CRCCode16[]={"CRCCode"};

	//TransmitTimeStamp[] = ReadTime();

				UCSR0B |=(1<<RXCIE0);//开USART0收中断
	
				UCSR1B |=(1<<TXCIE1);//开USART1发中断

								UART1_Transmit_String(CompayID);

								UART1_Transmit_String(DeviceCode);

								UART1_Transmit_String(TransmitTimeStamp);

								UART1_Transmit_String(DDC_Name);

								UART1_Transmit_String(NV_Name);

								UART1_Transmit_String(State);

								UART1_TransmitByte(data_up);

								//UART1_Transmit_String(UART0_RxBuf);

								UART1_Transmit_String(Space);

								UART1_Transmit_String(NVF);

								UART1_Transmit_String(CRCCode16);

								UART1_TransmitByte('
');

								UART1_TransmitByte('
');

				UCSR0B &=~(1<<RXCIE0); UCSR1B &=~(1<<TXCIE1);//关
		*/

     	unsigned char TransmitBuff[8] = {0};
	 	TransmitBuff[0] = 0x01;
     	TransmitBuff[1] = 0x03;
 		TransmitBuff[2] = 0x00;
 	 	TransmitBuff[3] = 0x00;

 	 	TransmitBuff[4] = 0x00;
     	TransmitBuff[5] = 0x0f;

		unsigned short wCrc = 0;
		wCrc = crc16(TransmitBuff, 6);

 	 	TransmitBuff[6] = (wCrc &0xFF00)>>8;
 	 	TransmitBuff[7] = (unsigned char)(wCrc &0x00FF);
		
		cli();//发送前清除所有中断

	 	UART0_Transmit_HEX(TransmitBuff,8);

		sei();//发送完成后打开中断

		//UCSR0B |= (1<<RXCIE0);
		UART0_ReceiveData();

		_delay_ms(30);
/*
		_delay_ms(20);
		_delay_ms(20);
		_delay_ms(20);
		_delay_ms(20);

		_delay_ms(20);
		_delay_ms(20);
		_delay_ms(20);
		_delay_ms(20);
*/

		cli();  

		UART1_Transmit_HEX(UART0_RxBuf,36); 

   		sei();  


	 	//_delay_ms(100);

	 //data_up=UART0_ReceiveByte();
/*
       unsigned char ReceiveBuff[128] = {0};

	 for (int n=0; n<35; n++)
	 	{
	 	    ReceiveBuff[n]=UART0_Receive();
	 	}
	 
	 UART1_Transmit_HEX(ReceiveBuff,35 );
*/
	 
}


//往设备发送数据
void SendDataDown(void)
{			
	
	//unsigned char data_down;

	//unsigned char CompayID[]={"shanghailianxun "};

	unsigned char DeviceCode[]={"DeviceCode "};

	unsigned char TransmitTimeStamp[]={"TimeStamp "};

	unsigned char DDC_Name[]={"DDC_0001 "};

	unsigned char NV_Name[]={"NV_001 "};

	unsigned char State[]={"State "};

	unsigned char Space[]={" "};

	unsigned char NVF[]={"NVF "};

	unsigned char CRCCode16[]={"CRCCode"};

					//data_down=UART1_ReceiveByte();
					//ReadTime();
					{
							UART0_Transmit_String(DeviceCode);

							UART0_Transmit_String(TransmitTimeStamp);

							UART0_Transmit_String(DDC_Name);

							UART0_Transmit_String(NV_Name);

							UART0_Transmit_String(State);

							//UART0_TransmitByte(data_down);

							UART0_Transmit_String(UART1_RxBuf);

							UART0_Transmit_String(Space);

							UART0_Transmit_String(NVF);

							UART0_Transmit_String(CRCCode16);

							UART0_TransmitByte('
');

							UART0_TransmitByte('
');

					}
}


int main(void)
{
	//unsigned char code str[] = "shanghailianxun";
	//unsigned char *pstr = str;
	//while(*pstr)
	//{
  		//send_a_char(*pstr);
  		//pstr ++;
	//}

     Initialize();
	 //PORTB=0xff;
	 //watchdog_on();

    //_delay_ms(100);
	//UART1_Transmit_String(string1);
	//UART1_TransmitByte('
');
	while(1)
		{
			//data_down=UART1_ReceiveByte();
			;
			//ReadHoldRegister();
			//SendDataDown();
		}
}

  

原文地址:https://www.cnblogs.com/timssd/p/4014812.html