RM0008 USB full speed device interface (USB)
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USB device address (USB_DADDR)
Address offset: 0x4C
Reset value: 0x0000
Buffer table address (USB_BTABLE)
Address offset: 0x50
Reset value: 0x0000
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Reserved EF ADD6 ADD5 ADD4 ADD3 ADD2 ADD1 ADD0
Res. rw rw rw rw rw rw rw rw
Bits 15:8 Reserved
Bit 7 EF: Enable Function
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.
Bits 6:0 ADD[6:0]: Device Address
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.
151413121110987654321 0
BTABLE[15:3] Reserved
rw rw rw rw rw rw rw rw rw rw rw rw rw Res.
Bits 15:3 BTABLE[15:3]: Buffer Table.
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 472).
Bits 2:0 Reserved, forced by hardware to 0.
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