USB Software Operating modes
Depending on the USB operating mode, the software should perform some of the follow-
ing operations:
Power On the USB interface
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Power-On USB pads regulator
Wait USB pads regulator ready state
Configure PLL interface
Enable PLL
Check PLL lock
Enable USB interface
Configure USB interface (USB speed, Endpoints configuration...)
Wait for USB VBUS information connection
Attach USB device
Power Off the USB interface
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Detach USB interface
Disable USB interface
Disable PLL
Disable USB pin regulator
Suspending the USB interface
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Clear Suspend Bit
Set USB suspend clock
Disable PLL
Be sure to have interrupts enable to exit sleep mode
Make the MCU enter sleep mode
Resuming the USB interface
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Enable PLL
Wait PLL lock
Clear USB suspend clock
Clear Resume information
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AT85C51SND3Bx
7632A–MP3–03/06
ATMEL [ ATMEL ]
