uart_to_twi_m8_组合._c

AVR单片机的T_TO_TWI通讯方式

/*****************************************************************
ICC-AVR application builder : 2005-8-19 14:40:53
 Target : M8
 Crystal: 7.3728Mhz
// Crystal: 4.6080Mhz

实验:做usart串行通讯实验
目的:了解及会使用usart串口
CPU:atmega8L
相关的5个寄存器:UCSRA,UCSRB,UCSRC,UDR,UBRR(UBRRH,UBRRL)
	         其中:UBRRH和UCSRC共用一个地址
******************************************************************/
/*配置:CKOPT=0,CKSEL3..0=1111,SUT1..0=11(65ms慢速上升电源)*/
#include <iom8v.h>
#include <macros.h>

//#define test

#define LED_ON   1
#define LED_OFF  0

#define IO_OUT_MAIN_LED   3 //PD3 pin1
#define IO_OUT_SLAVE_LED  2 //PD2 pin32

#define  Main_Led_Off()    PORTD |= BIT(IO_OUT_MAIN_LED)
#define  Slave_Led_Off()   PORTD |= BIT(IO_OUT_SLAVE_LED)
#define  Main_Led_On()     PORTD &= ~BIT(IO_OUT_MAIN_LED)
#define  Slave_Led_On()    PORTD &= ~BIT(IO_OUT_SLAVE_LED)
//usart
#define  Fosc_4608  // 选择4.608M晶振crystal
#define  true    1
#define  false   0

#ifdef  Fosc_73728
#define baudrate   47   //波特率为9600b/s    0<baudrate<255
#endif
#ifdef  Fosc_4608
#define baudrate  29 //波特率为9600b/s     0<baudrate<255
#endif
/* UART Buffer Defines */
#define UART_RX_BUFFER_SIZE 127
#define UART_TX_BUFFER_SIZE 127


//TWI
#define START 0x08 
#define RE_START 0x10
#define MT_SLA_ACK 0x18
#define MT_SLA_NOACK 0x20
#define MT_DATA_ACK  0x28
#define MT_DATA_NOACK 0x30
#define MR_SLA_ACK  0x40
#define MR_SLA_NOACK 0x48
#define MR_DATA_ACK 0x50
#define MR_DATA_NOACK 0x58
//常用TWI操作(主模式写和主模式读)
#define Start()    	  (TWCR=(1<<TWINT)|(1<<TWSTA)|(1<<TWEN))
#define Stop()     	  (TWCR=(1<<TWINT)|(1<<TWSTO)|(1<<TWEN))
#define Wait()	   	      while(!(TWCR&(1<<TWINT)))WDR()
#define TestAck() 	  (TWSR&0xf8)
#define SetAck()	      (TWCR|=(1<<TWEA))
#define SetNoAck()      (TWCR&=~(1<<TWEA))
#define Twi()	  	      (TWCR=(1<<TWEA)|(1<<TWINT)|(1<<TWEN))//含有响应位
#define Write8Bit(x)    {TWDR=(x);TWCR=(1<<TWINT)|(1<<TWEN);}



#define DEVICE_ADR  0x22

void check_I2C(void);
void init_data(void);
void port_init(void);
void init_devices(void);
void timer0_init(void);
void check_watchdog(void);
void process_data_pack(void);
void twi_transmint(void);
void watchdog_init(void);
void check_main_led(void);
void check_slave_led(void);
void ascii_to_hex(void);

unsigned char Twi_Hex_Data[3];
unsigned char Twi_ASCI_Data[6];
unsigned char Twi_Write_Flag,Twi_Read_Flag;
unsigned char Twi_ASCI_Data_Flag,Twi_Hex_Data_Flag;
//LED指示灯
unsigned char Slave_Led_Status;
unsigned char Main_Led_Status,Cur_Main_Led_Status,Count_10ms;
//usart
unsigned char UART_RX_buff[UART_RX_BUFFER_SIZE];
unsigned char UART_TX_buff[UART_TX_BUFFER_SIZE];
unsigned char Rx_Flag;
unsigned char Rx_Temp,Rx_Count;
unsigned char Rx_Start_Pack_Flag,Rx_Over_Pack_Flag;

unsigned char Write_Error[5] = {'x','w','4','0','x'};
unsigned char Read_Error[5]  = {'x','w','8','0','x'};



void main(void)
{
	init_devices();
	init_data();
    
	USART_Transmit( "read go!" );//用来指示,是不是看门狗复位
	while(1)  //forever
	   {
	      //while(1);
		  UART_Receive();
		 // while(1)WDR();
		  check_watchdog();//喂狗
	      process_data_pack();//解包
		  twi_transmint();
	      //while(1)WDR();
		  check_main_led();
		}
       
}
//>>>>>>>>>>>>>>>>>>>>>>>>解包
void process_data_pack(void)
{
   unsigned char cnt,dat;
   
   if(Rx_Over_Pack_Flag == true)
    {   
	    //从灯
		Slave_Led_Status = LED_ON;
		check_slave_led();//先让通讯亮一下
		Rx_Over_Pack_Flag = false;
		Slave_Led_Status = LED_OFF;
		
		if(UART_RX_buff[1] == 0x57)
		{
		   for(cnt =0;cnt<6;cnt++)
		    {
			   dat = UART_RX_buff[cnt+2];
			   if((dat >= 0x30)&&(dat <=0x39))
			    {
				  Twi_ASCI_Data[cnt] = dat - 0x30;
				}
			   else if((dat>=0x41)&&(dat<=0x46))
			    {
				  Twi_ASCI_Data[cnt] = dat - 0x37;//如果是字母,那么减去0x37
				}
		    }
			ascii_to_hex();//组合成数据
		   Twi_Write_Flag = true;
		}
		if(UART_RX_buff[1] == 0x52)
		{
		   for(cnt =0;cnt<4;cnt++)
		    {
			   dat = UART_RX_buff[cnt+2];
			   if((dat >= 0x30)&&(dat <=0x39))
			    {
				  Twi_ASCI_Data[cnt] = dat - 0x30;
				}
			   else if((dat>=0x41)&&(dat<=0x46))
			    {
				  Twi_ASCI_Data[cnt] = dat - 0x37;//如果是字母,那么减去0x37
				}
		    }
			ascii_to_hex();
		   Twi_Read_Flag = true;
		}
		Twi_Hex_Data_Flag = true;
		//处理完,先把数据放在UART_TX_buff[]绶冲区,且接收绶冲区清零
		/*for(cnt=0;cnt<9;cnt++)
		{
		   UART_TX_buff[cnt] = UART_RX_buff[cnt];
		   UART_RX_buff[cnt] = 0;
		}*/
		
	}
}
//继续解包,=>两个ASCII码组成一个数
void ascii_to_hex(void)
{
    unsigned char cnt,i;
   
	for(cnt=0,i=0;cnt<6;cnt++,cnt++,i++)
	{
	  Twi_Hex_Data[i] = Twi_ASCI_Data[cnt+1];//先放ASCII的高位(四位)
	  Twi_Hex_Data[i] <<= 4;
	  Twi_Hex_Data[i] += Twi_ASCI_Data[cnt];
	}
}
void hex_to_ascii(unsigned char dat)
{
    unsigned char dat_buff;
  
    dat_buff = dat;
    dat = dat&0x0f;
    if((dat>=0)&&(dat<=9))
    {
       dat += 0x30;
    }
    else
       dat += 0x37;
	UART_TX_buff[7] = dat;
	  
    dat = dat_buff;
	dat >>= 4;
	dat = dat&0x0f;
    if((dat>=0)&&(dat<=9))
    {
      dat += 0x30;
    }
    else
      dat += 0x37;
	UART_TX_buff[8] = dat;
}
//<<<<<<<<<<<<<<<<<<<<<
/***********************************************************************
通用的hex转成ascii
************************************************************************/
unsigned char general_hex_to_ascii(unsigned char dat)
{
    dat = dat & 0x0f;
    if((dat >= 0)&&(dat <= 9))
    {
	  dat = dat + 0x30;
	}
	else if((dat>='A')&&(dat<='F'))
	{
	  dat += dat + 0x37;
	}
	return dat;
}

//>>>>>>>>>>>>>>>>做包
void twi_transmint(void)
 {
    unsigned char dat1,dat2;
	unsigned char dat1_buff;
  
    if(Twi_Hex_Data_Flag == true)
    {
	    
	    Twi_Hex_Data_Flag = false;
		if(Twi_Write_Flag == true)
		{
		    Twi_Write_Flag = false;
	        dat1 = twi_Write(Twi_Hex_Data[0],Twi_Hex_Data[1],Twi_Hex_Data[2]);
		
		    #ifdef test
		    dat1_buff = dat1;
		    dat1 >>= 4;
		    dat1 = dat1 & 0x0f;
		    dat1 = general_hex_to_ascii( dat1 );
			USART_TransmitByte(dat1);
			dat1 = dat1_buff;
			dat1 = dat1 & 0x0f;
			dat1 = general_hex_to_ascii( dat1 );
			USART_TransmitByte(dat1);
			#endif
		
			if(dat1 == 0)
			{
				USART_Transmit(UART_RX_buff);//写成功
			}
			else
			{
				USART_Transmit(Write_Error);//写不成功
			}	
	    
			#ifdef test 
			USART_Transmit("ok!");
			//while(1)WDR();
			#endif
		}
		if(Twi_Read_Flag == true)
        {
			#ifdef test
			USART_TransmitByte((Twi_Read_Flag+0x30));
			USART_Transmit("yes or no?");
			#endif
		
			Twi_Read_Flag = false;
			dat2 = twi_Read(Twi_Hex_Data[0],Twi_Hex_Data[1]);
			if(dat2 == 0)
			{
				USART_Transmit(Read_Error);//读失败
				#ifdef test
				USART_Transmit("here!");
				#endif
			}
			else
			{
				hex_to_ascii(dat2);//读成功 且读的数在dat2中
				USART_Transmit(UART_RX_buff);
			}
		
			#ifdef test
			USART_Transmit("verify again!");
			#endif
		}
	}
 }

void init_data(void)
{
   Twi_Write_Flag     = false;
   Twi_Read_Flag      = false;
   Twi_Hex_Data_Flag  = false;      
   Twi_ASCI_Data_Flag = false;
   Slave_Led_Status   = LED_OFF;
   Main_Led_Status    = LED_OFF;
   Cur_Main_Led_Status= LED_OFF;
   Count_10ms         = 0;
   WDR();
}
void port_init(void)
{
 PORTB = 0x3F;
 DDRB  = 0x00;
 PORTC = 0x4F; //m103 output only
 DDRC  = 0x00;
 PORTD = 0xFC;
 DDRD  = 0x00;
}
//call this routine to initialize all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();
 uart0_init();
 twi_init();
 timer0_init();
 watchdog_init();

 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x00; //timer interrupt sources
 SEI(); //re-enable interrupts
 //all peripherals are now initialized
}
void check_watchdog(void)
{
 	WDR();//喂狗
}
void watchdog_init(void)
{
 WDR();//看门狗计数清零
 WDTCR=((1<<WDE)|(1<<WDP2)|(1<<WDP0));//64K分频,0.52S
 //WDIE是看门狗中断使能,WDE看门狗使能 101 512k
}

//TIMER0 initialize - prescale:256
// desired value: 100Hz
// actual value: 100.000Hz (0.0%)
void timer0_init(void)
{
 TCCR0 = 0x00; //stop
 TCNT0 = 0x4C; //set count
 TCCR0 = 0x04; //start timer
}

#pragma interrupt_handler timer0_ovf_isr:10
void timer0_ovf_isr(void)
{
    TCNT0 = 0x4C; //reload counter value
    //主灯
    Count_10ms++;
    if((Count_10ms>0)&&(Count_10ms<5))
    {
       Cur_Main_Led_Status = LED_ON;
	}
    if((Count_10ms>5)&&(Count_10ms<10))
    {
      Cur_Main_Led_Status = LED_OFF;
    }
}
void check_main_led(void)
{
   if(Main_Led_Status != Cur_Main_Led_Status)
   {
 	  if(Main_Led_Status == LED_ON) 	   Main_Led_Off();
	  else		   	  		   	   Main_Led_On();
	  Main_Led_Status = Cur_Main_Led_Status;
   }
}
void check_slave_led(void)
{
    if(Slave_Led_Status == LED_ON) 
    {
      Slave_Led_On();
	}
	else		   	  		   	  
    {
      Slave_Led_Off();
    }
}

void twi_init(void)
{
 TWCR= 0X00; //disable twi
 TWBR= 0x20; //set bit rate
 TWSR= 0x00; //set prescale
 TWAR= DEVICE_ADR; //set slave address
 TWCR= 0x44; //enable twi 置位TWEA,TWEN TWIE
}
/******************************************
                I2C总线写一个字节
			    返回0:       写成功
				返回错误状态字:写失败
*******************************************/
unsigned char twi_Write(unsigned char wr_device_add,unsigned char RamAddress,unsigned char Wdata) 
{
	  Start();//I2C启动
	  Wait(); //等TWINT置位
	  if(TestAck()!=START) return TestAck();//ACK
	  Write8Bit(wr_device_add);//写I2C从器件地址和写方式
	  Wait();
	  if(TestAck()!=MT_SLA_ACK) return TestAck();//ACK
	  Write8Bit(RamAddress);//写RAM地址
	  Wait();
	  if(TestAck()!=MT_DATA_ACK) return TestAck();//ACK
	  Write8Bit(Wdata);//写数据
	  Wait();
	  if(TestAck()!=MT_DATA_ACK) return TestAck();//ACK	
	  Stop();//I2C停止
 	  delay_ms(10);//延时等写完
	  return 0;
}
/******************************************
               I2C总线读一个字节
			   如果读失败也返回0
*******************************************/
unsigned char twi_Read(unsigned char rd_device_add,unsigned char RamAddress) 
    {
	   unsigned char temp;
	   Start();//I2C启动
	   Wait();
	   if (TestAck()!=START) return 0;//ACK	   
	   Write8Bit(rd_device_add);//写I2C从器件地址和写方式
	   Wait(); 
	   if (TestAck()!=MT_SLA_ACK) return 0;//ACK
	   Write8Bit(RamAddress);//写RAM地址
	   Wait();
	   if (TestAck()!=MT_DATA_ACK) return 0;
	   Start();//I2C重新启动
	   Wait();
	   if (TestAck()!=RE_START)  return 0;
	   Write8Bit(rd_device_add+1);//写I2C从器件地址和读方式
	   Wait();
	   if(TestAck()!=MR_SLA_ACK)  return 0;//ACK
	   Twi();//启动主I2C读方式,且设为准备响应
	   Wait();
	   if(TestAck()!=MR_DATA_NOACK) return 0;//ACK	
	   temp=TWDR;//读取I2C接收数据
       Stop();//I2C停止
	   return temp;
    }
#pragma interrupt_handler uart0_rx_isr:12
void uart0_rx_isr(void)
{
   //uart has received a character in UDR
  
	UART_RX_buff[Rx_Count] = UDR;
    Rx_Count = Rx_Count+1;
    if(Rx_Count == 9)
       {
          Rx_Flag  = true; 
	      //USART_TransmitByte((Rx_Count+0x30));
		  Rx_Count = 0;
		  //上位机在这时候要停一会儿，才能发第二串数据
	   }
	//USART_TransmitByte((Rx_Count+0x30));
}

//UART0 initialize
// desired baud rate: 9600
// actual: baud rate:9600 (0.0%)
// char size: 8 bit
// parity: Disabled
void uart0_init(void)
{
 Rx_Count = 0;
 Rx_Flag  = false;
 Rx_Start_Pack_Flag = false;
 Rx_Over_Pack_Flag  = false;
 //本身的uart的初始化
 UCSRB = 0x00; //disable while setting baud rate
 //UCSRB[RXCIE,TXCIE,UDRIE,RXEN,TXEN,UCSZ2,RXB8,TXB8]
 //Bit 7 – RXCIE: RX Complete Interrupt Enable

 UCSRA = 0x00;
 //UCSRA[RXC,TXC,UDRE,FE,DOR,PE,U2X,MPCM]
 
 UCSRC = (BIT(URSEL)|BIT(UCSZ1)|BIT(UCSZ0));//设置成8位
 //UCSRC[URSEL,UMSEL,UPM1,UPM0,USBS,UCSZ1,UCSZ0,UCPOL]
 //位URSEL:寄存器选择("1"为UCSRC或"0"为UBRRH)
 //位UMSEL:工作模式选择(0为异步,1为同步)
 //位UPM1..0:为校验方式,硬件支持校验
 //位USBS:停止位选择(0为一位,1为两位)
 //位UCSZ0..2:发送位数选择(如果是8位:011)
 //位UCPOL:时钟极性(只在同步模式使用,异步应置为"0")
 
 UBRRL = baudrate; //set baud rate lo
 UBRRH = 0x00; //set baud rate hi(设置波特率只用低四位,加起来一共12位)
 //UBRR = baudrate; /* set the baud rate */

 UCSRB = ((1<<RXCIE)|(1<<RXEN)|(1<<TXEN));
}
/************************************************************************
接收时采用中断方式,,,以"包"为单位接收(9个字符)
*************************************************************************/
void UART_Receive(void)
{
   if(Rx_Flag == true)
    {
   		Rx_Flag = false;
		
		if((UART_RX_buff[0] == 0x58)&&(UART_RX_buff[8] == 0x58))//0x58  = 'w'
        {
			Rx_Over_Pack_Flag  = true;      //这个标志,可以让主函数去查
			//Rx_Count = 0;//接收计数器清零
		}
		//USART_TransmitByte('p');//接收一包完,就发一个信号叫上机暂停发