本帖最后由 STARM 于 2013-4-22 22:55 编辑
关于VBUS的连接,最清晰的解释在参考手册内,如下:
The VBUS pin can be freed by disabling the VBUS sensing option.
This is done by setting the NOVBUSSENS bit in the OTG_FS_GCCFG register.
In this case the VBUS is considered internally to be always at VBUS valid level (5 V).
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