I tried to use the I2C of MSP430F6736 as the master I2C device. I found very weird stuff during the code debugging. I could see the SCL line has the 9 clock pulse. I also could see the start bit in the SDA line. But I just couldn't get the data output from the SDA line (so there would be no ACK from slave). The SDA is hold low during the whole byte transmit stage (See figure below). Even I removed the slave device from the picture. It still has the same result. What could cause this weird issue? I have checked the UCB0TXBUF register got what it shall get (such as 0x55).
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