ST STM32F40 Series Reference Manual page 1053

USB on-the-go full-speed (OTG_FS)
Bit 18 ADTOCHG: A-device timeout change
The core sets this bit to indicate that the A-device has timed out while waiting for the B-device
to connect.
Note: Accessible in both device and host modes.
Bit 17 HNGDET: Host negotiation detected
The core sets this bit when it detects a host negotiation request on the USB.
Note: Accessible in both device and host modes.
Bits 16:10 Reserved, must be kept at reset value.
Bit 9 HNSSCHG: Host negotiation success status change
The core sets this bit on the success or failure of a USB host negotiation request. The
application must read the host negotiation success bit of the OTG_FS_GOTGCTL register
(HNGSCS in OTG_FS_GOTGCTL) to check for success or failure.
Note: Accessible in both device and host modes.
Bits 7:3 Reserved, must be kept at reset value.
Bit 8 SRSSCHG: Session request success status change
The core sets this bit on the success or failure of a session request. The application must
read the session request success bit in the OTG_FS_GOTGCTL register (SRQSCS bit in
OTG_FS_GOTGCTL) to check for success or failure.
Note: Accessible in both device and host modes.
Bit 2 SEDET: Session end detected
The core sets this bit to indicate that the level of the voltage on V
Peripheral session when V
Bits 1:0 Reserved, must be kept at reset value.
1053/1422
< 0.8 V.
BUS
Doc ID 018909 Rev 4
RM0090
is no longer valid for a B-
BUS