STM32F101xx, STM32F102xx, STM32F103xx, STM32F105xx and ...

USB on-the-go full-speed (OTG_FS)
RM0008
26.14.4 Device-mode registers
OTG_FS device configuration register (OTG_FS_DCFG)
Address offset: 0x800
Reset value: 0x0220 0000
This register configures the core in Device mode after power-on or after certain control
commands or enumeration. Do not make changes to this register after initial programming.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Reserved
PFIVL
DAD
Reserved
NZLSOHSK
DSPD
rw rw rw rw rw rw rw rw rw rw rw
Bits 31:13 Reserved
Bits 12:11 PFIVL: Periodic frame interval
Indicates the time within a frame at which the application must be notified using the end of
periodic frame interrupt. This can be used to determine if all the isochronous traffic for that
frame is complete.
00: 80% of the frame interval
01: 85% of the frame interval
10: 90% of the frame interval
11: 95% of the frame interval
Bits 10:4 DAD: Device address
The application must program this field after every SetAddress control command.
Bit 3 Reserved
Bit 2 NZLSOHSK: Non-zero-length status OUT handshake
The application can use this field to select the handshake the core sends on receiving a
nonzero-length data packet during the OUT transaction of a control transfer’s Status stage.
1: Send a STALL handshake on a nonzero-length status OUT transaction and do not send
the received OUT packet to the application.
0: Send the received OUT packet to the application (zero-length or nonzero-length) and
send a handshake based on the NAK and STALL bits for the endpoint in the Device endpoint
control register.
Bits 1:0 DSPD: Device speed
Indicates the speed at which the application requires the core to enumerate, or the maximum
speed the application can support. However, the actual bus speed is determined only after the
chirp sequence is completed, and is based on the speed of the USB host to which the core is
connected.
00: Reserved
01: Reserved
10: Reserved
11: Full speed (USB 1.1 transceiver clock is 48 MHz)
754/995 Doc ID 13902 Rev 9