用数据窗口实现指针式时钟，环境：PB9.0 可以用数据窗口实现很多功能，此处就为一列。 你可以在程序的任何地方通过open(w_clock)显示此时钟。 -Analog clock with the data window to achieve the environment: PB9.0 can use the data window to achieve a lot of features, here on the one. You can anywhere in the pr