ST STM32G4 Series Reference Manual page 1982

Universal serial bus full-speed device interface (USB)
Bit 11 SUSPM: Suspend mode interrupt mask
Bit 10 RESETM: USB reset interrupt mask
Bit 9 SOFM: Start of frame interrupt mask
Bit 8 ESOFM: Expected start of frame interrupt mask
Bit 7 L1REQM: LPM L1 state request interrupt mask
Bit 6 Reserved, must be kept at reset value.
Bit 5 L1RESUME: LPM L1 Resume request
Bit 4 RESUME: Resume request
Bit 3 FSUSP: Force suspend
Bit 2 LP_MODE: Low-power mode
1982/2083
0: Suspend Mode Request (SUSP) Interrupt disabled.
1: SUSP Interrupt enabled, an interrupt request is generated when the corresponding bit in
the USB_ISTR register is set.
0: RESET Interrupt disabled.
1: RESET Interrupt enabled, an interrupt request is generated when the corresponding bit in
the USB_ISTR register is set.
0: SOF Interrupt disabled.
1: SOF Interrupt enabled, an interrupt request is generated when the corresponding bit in the
USB_ISTR register is set.
0: Expected Start of Frame (ESOF) Interrupt disabled.
1: ESOF Interrupt enabled, an interrupt request is generated when the corresponding bit in
the USB_ISTR register is set.
0: LPM L1 state request (L1REQ) Interrupt disabled.
1: L1REQ Interrupt enabled, an interrupt request is generated when the corresponding bit in
the USB_ISTR register is set.
The microcontroller can set this bit to send a LPM L1 Resume signal to the host. After the
signaling ends, this bit is cleared by hardware.
The microcontroller can set this bit to send a Resume signal to the host. It must be activated,
according to USB specifications, for no less than 1 ms and no more than 15 ms after which
the Host PC is ready to drive the resume sequence up to its end.
Software must set this bit when the SUSP interrupt is received, which is issued when no
traffic is received by the USB peripheral for 3 ms.
0: No effect.
1: Enter suspend mode. Clocks and static power dissipation in the analog transceiver are left
unaffected. If suspend power consumption is a requirement (bus-powered device), the
application software should set the LP_MODE bit after FSUSP as explained below.
This mode is used when the suspend-mode power constraints require that all static power
dissipation is avoided, except the one required to supply the external pull-up resistor. This
condition should be entered when the application is ready to stop all system clocks, or
reduce their frequency in order to meet the power consumption requirements of the USB
suspend condition. The USB activity during the suspend mode (WKUP event)
asynchronously resets this bit (it can also be reset by software).
0: No Low-power mode.
1: Enter Low-power mode.
RM0440 Rev 1
RM0440