ST STM32F101 series Reference Manual page 634

RM0008
USB device address (USB_DADDR)
Address offset: 0x4C
Reset value: 0x0000
15 14 13 12
Bits 15:8 Reserved
Bit 7 EF: Enable function
Bits 6:0 ADD[6:0]: Device address
Buffer table address (USB_BTABLE)
Address offset: 0x50
Reset value: 0x0000
15 14 13
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Bits 15:3 BTABLE[15:3]: Buffer table
Bits 2:0 Reserved, forced by hardware to 0.
11 10 9
Reserved
This bit is set by the software to enable the USB device. The address of this device is
contained in the following ADD[6:0] bits. If this bit is at '0 no transactions are handled,
irrespective of the settings of USB_EPnR registers.
These bits contain the USB function address assigned by the host PC during the
enumeration process. Both this field and the Endpoint Address (EA) field in the associated
USB_EPnR register must match with the information contained in a USB token in order to
handle a transaction to the required endpoint.
12 11 10 9
BTABLE[15:3]
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These bits contain the start address of the buffer allocation table inside the dedicated packet
memory. This table describes each endpoint buffer location and size and it must be aligned
to an 8 byte boundary (the 3 least significant bits are always '0). At the beginning of every
transaction addressed to this device, the USP peripheral reads the element of this table
related to the addressed endpoint, to get its buffer start location and the buffer size (Refer to
Structure and usage of packet buffers on page
Universal serial bus full-speed device interface (USB)
8 7 6
EF ADD6
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8 7 6
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617).
DocID13902 Rev 15
5 4 3 2
ADD5 ADD4 ADD3 ADD2
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5 4 3 2
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1 0
ADD1 ADD0
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1 0
Reserved
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