版本 3abae8cb30e25cf53ff6674ca506824e44869a24
Changes from 3abae8cb30e25cf53ff6674ca506824e44869a24 to 2b7b863eaf54fb4e791f48d15ab135b4553a7780
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title: usb
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temporal notes
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AHB(Advanced High-performance Bus)
1. AHB(Advanced High-performance Bus)
2. reference manual 30.3.2
- DP/DM integrated pull-up and pull-down resistors controlled by the OTG_FS core depending on the current role of the device. As a peripheral, it enables the DP pull-up resistor to signal full-speed peripheral connections as soon as VBUS is sensed to be at a valid level (B-session valid).
- In host mode, pull-down resistors are enabled on both DP/DM. Pull-up and pull-down resistors are dynamically switched when the device’s role is changed via the host negotiation protocol (HNP).
