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Problem with I2C mode of 16f877a

I am having problem with I2C mode of 16f877a. I wrote a code for I2C ranging mode of the SRF02 sensors. At first I thought the problem was with the code, but then I debugged the circuit a little; the code is as below:

int main(){

TRISB = 0x00; //Port B is output
TRISD = 0x00; //Port D is output

//Get the range
I2C_Start(void); // send start sequence
I2C_Wr(0xE0); // SRF02 I2C address with R/W bit clear
I2C_Wr(0x00); // SRF02 command register address
I2C_Wr(0x81); // command to start ranging in cm
I2C_Stop(void); // send stop sequence

delay_ms(70); //delay for 70ms.

I2C_Start(void); // send start sequence
I2C_Wr(0xE0); // SRF02 I2C address with R/W bit clear
I2C_Wr(0x02); // send internal adress of high byte.

I2C_Repeated_Start(void); // send a restart sequence
I2C_Wr(0xE1); // SRF02 I2C address with R/W bit set

PORTB=I2C_Rd(1); // get the high byte of the range and send acknowledge.
PORTC=I2C_Rd(0); // get low byte of the range - note we don't acknowledge the last byte.

I2C_Stop(void); // send stop sequence

return 0;

This code would normally first of all make a PIC generate a clock on the CLK pin of the PIC (I think this is what I2C_Init() command does). But I observed on Scope that there is no clock on this pin. I only observed 5V dc. I heard that 16f877a PICs have problems with i2c, and now I observe that it simply does not generate clock. 

PS: I also wrote MIKROC's example simple code to the PIC to eliminate my mistakes, just to check the presence of the clock. Still, I could not see it. My final conclusion is: 16f877a does not generate clock in I2C mode.=> no i2c operation is possible?

Does anyone has similar problem? Should I change the Microcontroller?  

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It is OK, the problem is solved. my compiler had a problem I think. I tried to compile the code on another compiler it worked!
Yes, clock is  RC3/SCK/SCL pin of 16f877a. Oscillator configuration (under this I assume the oscillator selected when programming the PIC) is HS.  I have tried 100KHz as well, but still no clock, only DC level signal. And about the interference with I2C pins: I made PORTD=I2C_Rd(0) instead of  PORTC=I2C_Rd(0), still the same. Also by debugging I observed that the process stops on the operation I2C_Wr(0xE0), I think it is not able to write (most probably because of absence of clock).

By 'CLK' do you mean RC3/SCK/SCL? What is your oscillator configuration? What are you using to measure the I2C clock frequency? 2MHz is pretty fast, have you tried using a slower clock option?
Make sure your PORTB=I2C_Rd(1); and PORTC=I2C_Rd(0); commands aren't interfering with the I2C pins.