I found something very strange in my board.I used a mcf52259 as the cpu and configued it as an i2c master,when power on, ,the SCL and SDA line were all 1 level. But after the I2C enable code excuted,the SCL and SDA line were all turned to 0. When I tried to send some data out,the the scope could catch the data and clk so I know the MCU is still running.But why the two line are low level in the idle time?
I have checked hardware design,there is no different with the other i2c design at all !
Any one had met the same problem?