[SOLVED] Spurious scl transition error in pic18f6722 i2c code

[Logu KS]

/* I2C */

/* Header file */

#include<pic18.h>
#include<TIMER.h>
#define _XTAL_FREQ 4E6

void I2Cinit(void);
void I2Cstart(void);
void I2Cstart(void);
void I2Cstop(void);
void I2CsendACK(void);
void I2CsendNACK(void);
void I2Cwait(void);
void I2Csend(unsigned char dat);
bit I2Cwritebyte(unsigned char dat);
unsigned char I2Creadbyte(unsigned char ack);

/* I2C Functions */

void I2Cinit(void)
{	
	TRISC3 = 1;					// SCK as input
	TRISC4 = 1;					// SDA as input
	SSP1STAT |= 0x80;			// Slew rate control enable for high speed mode for standard speed
	SSP1CON1 = 0x38;				// I2C master mode and SCK and SDA as serial pins
	SSP1CON2 = 0x00;
	SSP1ADD = 9;
}

void I2Cstart(void)
{
	I2Cwait();
	SEN = 1;					// Start enable bit
	//SSPCON2 bit 0
	while (SEN == 1);
}

void I2Crestart(void)
{
	I2Cwait();
	RSEN = 1;					// Restart enable bit
	//SSPCON2 bit 1
	while (RSEN == 1);
}

void I2Cstop(void)
{
	I2Cwait();
	PEN=1;						// Stop enable bit
	while(PEN==1);
	//continue;
}

void I2CsendACK(void)
{
	ACKDT = 0;					// 0 = ACK
	ACKEN = 1;					// Sending ack
	while(ACKEN);
}

void I2CsendNACK(void)
{
	ACKDT = 1;					// 1 = NACK
	ACKEN = 1;					// Sending nack
	while(ACKEN);
}

void I2Cwait(void)
{
	while ( ( SSP1CON2 & 0x1F ) || ( SSP1STAT & 0x04 ) );
}

void I2Csend(unsigned char dat)
{
	SSP1BUF = dat; 
    while(BF);      
    I2Cwait();      
}

bit I2Cwritebyte(unsigned char dat)
{
	SSP1BUF = dat;    
    while(BF);      
	return 0;
    //I2Cwait();      
}

unsigned char I2Creadbyte(unsigned char ack)
{
 	unsigned char temp;
 	I2Cwait();
 	RCEN=1;
 	I2Cwait();
 	temp = SSP1BUF;
 	I2Cwait();
 	if (ack)ACKDT=0;
 	else ACKDT=1;
 	ACKEN=1; 
 	return( temp );
}

/* Main */

void main()
{
	I2Cinit();
	I2Cstart();
	I2Csend('M');
	I2CsendACK();
	I2Cstop();
	while(1)
	{}
}

this is my i2c code while compiling there is no error and warning in mplab ide

when i put it in proteus it is showing spurious scl transition detected...

 

[milan.rajik]

You can try setting TRISC3 and TRISC4 as outputs. Also you can use I2C_wait() between each I2C function called.

 

[Logu KS]

i tried by using I2C_wait function in between the function calls....

but same thing is happening in the proteus

 

[milan.rajik]

Zip and post your complete MPLAB 8 project files. Which version of Hi-Tech C Compiler are you using ?

 

[Logu KS]

i am using hightech c pro for the PIC18 family v9.65 and MPLAB v.8.56

- - - Updated - - -

I also tried the i2c.h peripheral library file. While using it there is an error....

Error [499] ; 0. undefined symbol:
_putsI2C1(I2C.obj)

 

[milan.rajik]

Try the Hi-Tech PICC I2C example provided at

https://saeedsolutions.blogspot.com

 

[Logu KS]

The problem is solved in mplabx ide and xc8 compiler.....
While compiling the code in xc8 compilere there are no spurious transition errors in proteus..