void i2c_stop (void)
{
   unsigned char input_var;

   SCLK      = LOW;    // Set clock line low
   SDATA     = LOW;    // Set data line low
   SCLK      = HIGH;   // Set clock line high
   SDATA     = HIGH;   // Set data line high (STOP SIGNAL)
   input_var = SDATA;  // Put port pin into HiZ
}