update usb rst

2022-06-26 18:40:00 +08:00
parent 9bd3c00b8c
commit 64ee6877e5
5 changed files with 28 additions and 2 deletions
--- a/docs/source/usb/usb_desc.rst
+++ b/docs/source/usb/usb_desc.rst
@@ -1,6 +1,8 @@
 USB 描述符
 ===========================

+本节参考官方 usb2.0 pdf 9.5 节即可。
+
 设备描述符
 ---------------------