drvi2c.c

本人编写的无线电话程序,给予PIC18C801设计,包括了uCOS的移植以及菜单,自己设计的拼音注入法,完整地一级汉字库,希望对大家有所帮助

#include "includes.h"
#include "fi2c.h"
#include "device.h"
#include "hardware.h"

INT16U i2c_init(void);
INT16U i2c_open(void);
INT16U i2c_write( INT8U rom *wrptr, INT16U length );
INT16U i2c_read( INT8U rom *rdptr, INT16U length );
INT16U i2c_ioctl(INT8U cmd, INT24U arg);

#pragma romdata CCODE
DEV_HEADER DEV_I2C = {
	DEV_ID_I2C,				/*device ID  */
	{'i','2','c'},			/*device name*/
	DEVP_CHAR,				/*device Type*/
	i2c_init,				/*device init function*/
	FNull_1,				/*device clear function*/
	i2c_open,				/*device open function*/
	FNull_1,				/*device close function*/
	i2c_ioctl,				/*device ioctl function*/
	i2c_write,				/*device write function*/
	i2c_read				/*device read function*/
};

#pragma code MYCODE
INT16U i2c_init(void){
	//set basic parameters of the i2c interface
	//currently do nothing
}

INT16U i2c_open(void){
	SSPSTATbits.SMP = 0;
	SSPCON1 = 0x08;			//select I2C master mode
	SSPCON1bits.SSPEN = 1;	//enable I2C 
	PIR2bits.BCLIF = 0;
	
	SSPADD = 10;		 
	
	WP = 0;		//Enable write to eeprom
}

INT16U i2c_write( INT8U rom *wrptr, INT16U length ){
	while (length) {
    	if ( SSPCON1bits.SSPM3 ){      // if Master transmitter then execute the following
      		if ( putcI2C ( *wrptr ) ){   // write 1 byte
		        return ( 0xff );            // return with write collision error
		      }
			IdleI2C();                  // test for idle condition
      		length--;
      		if ( SSPCON2bits.ACKSTAT ){  // test received ack bit state
	        	return ( 0xfe );            // bus device responded with  NOT ACK
    		}                           // terminate putsI2C() function
    	}

    	else{                          // else Slave transmitter
      		PIR1bits.SSPIF = 0;         // reset SSPIF bit
      		SSPBUF = *wrptr;            // load SSPBUF with new data
      		SSPCON1bits.CKP = 1;        // release clock line 
      		while ( !PIR1bits.SSPIF );  // wait until ninth clock pulse received
      		if ( ( !SSPSTATbits.R_W ) && ( !SSPSTATbits.BF ) ){ // if R/W=0 and BF=0, NOT ACK was received
        		return ( 0xfd );            // terminate PutsI2C() function
      		}
    	}
  		wrptr ++;                       // increment pointer
  	}                               // continue data writes until null character
  	return ( 0 );
}

INT16U i2c_read( INT8U rom *rdptr, INT16U length )
{
	INT16U len;
	len = length;
    while ( length -- ){           // perform getcI2C() for 'length' number of bytes
    	*rdptr++ = getcI2C();       // save byte received
      	while ( SSPCON2bits.RCEN ); // check that receive sequence is over    
    	if ( PIR2bits.BCLIF ) return ( 0 );       // test for bus collision
    	if ( length ){               // test if 'length' bytes have been read
	        SSPCON2bits.ACKDT = 0;    // set acknowledge bit state for ACK        
    	    SSPCON2bits.ACKEN = 1;    // initiate bus acknowledge sequence
        	while ( SSPCON2bits.ACKEN ); // wait until ACK sequence is over 
      	} 
    }
    return (len);                 // last byte received so don't send ACK      
}

INT16U i2c_ioctl(INT8U cmd, INT24U arg){
	switch(cmd){
		case I2C_RESTART:
			RestartI2C();
			while ( SSPCON2bits.RSEN ); 
			break;
		case I2C_NOTACK:
			NotAckI2C(); 
			while ( SSPCON2bits.ACKEN );
			break;
		case I2C_STOP:
			StopI2C();
			while ( SSPCON2bits.PEN );
			break;
		case I2C_BUSSTT:
			if(PIR2bits.BCLIF){
				PIR2bits.BCLIF = 0;
				return(1);
			}
			return(0);
			break;
		case I2C_START:
			StartI2C();
			while ( SSPCON2bits.SEN );
			break;
		case I2C_IDLE:
			IdleI2C();
			break;
	}
}