My friend's USB port has a strange question: if the USB peripheral is turned on, the USB port will not respond, for example, insert the USB keyboard to turn it on, the keyboard is not used at all after the boot is turned on. And my machine There is a similar more interesting phenomenon: inserting a USB peripheral boot, the machine can not open! Or in the process of booting the USB peripheral, then the machine stops, just like pressing the Pause button! Regardless of this problem, it reminds me of the principle of C and Java's error. C tend to kill the mistake in the cradle, try to make the error in the compile period, do not let them slip into the runtime, Java is " Exception Crazy, if there is a mistake, the most likely result is that the running period gives you a bunch of abnormalities, you slowly find it! After you have to compile, restart the program, and the Java program starts like the old woman The head is like, the slow is heartbeat :- (my machine is like C , there is peripheral (wrong) on the USB port (wrong) simply do not let you boot. And the friend's machine is a quiet, let the machine continue to run. It will not be found until you use a USB peripheral! - God, you have to restart!
