分享到plurk 分享到twitter 分享到facebook

版本 0369734ab0a98c113858f8471d86f4e20b326fbb

usb

temporal notes ^^^^^^^^^^^^^^^ 1. AHB(Advanced High-performance Bus) 2. DP/DM description – in 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).