I2C协议有如下一段话：
There is an undefined condition if the arbitration procedure is still in progress at the moment when one master sends a repeated START or a STOP condition while the other master is still sending data. In other words, the following combinations result in an undefined condition:
• Master 1 sends a repeated START condition and master 2 sends a data bit.
• Master 1 sends a STOP condition and master 2 sends a data bit.
• Master 1 sends a repeated START condition and master 2 sends a STOP condition.
如果出现了图中说的3种情况，I2C总线上实际发生了什么？
