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]!='\0')
- i++;
- while(s2[j]!='\0')
- s1[i++]=s2[j++];
- s1[i]='\0';
- 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('\r');
- UART1_TransmitByte('\n');
- 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('\r');
- UART0_TransmitByte('\n');
- }
- }
- 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('\n');
- while(1)
- {
- //data_down=UART1_ReceiveByte();
- ;
- //ReadHoldRegister();
- //SendDataDown();
- }
- }
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