R01UH0823EJ0100 Rev.1.00
Page 932 of 1823
Jul 31, 2019
RX23W Group
32. USB 2.0 Host/Function Module (USBc)
32.3.3.6
Frame Update Interrupt
With the host controller selected, an interrupt is generated at the timing when the frame number is updated. With the
function controller selected, an SOFR interrupt is generated when the frame number is updated.
When the function controller is selected, the USB updates the frame number and generates an SOFR interrupt if it detects
a new SOF packet during full-speed operation.
32.3.3.7
VBUS Interrupt
When the USB0_VBUS pin level changes, a VBUS interrupt is generated. The level of the USB0_VBUS pin can be
checked with the INTSTS0.VBSTS flag. Whether the host controller is connected or disconnected can be confirmed
using the VBUS interrupt. However, if the system is activated with the host controller connected, the first VBUS
interrupt is not generated because there is no change in the USB0_VBUS pin level.
32.3.3.8
Resume Interrupt
When the function controller is selected, a resume interrupt is generated when the device state is the suspended state and
the USB bus state has changed (from J-state to K-state, or from J-state to SE0). Recovery from the suspended state is
detected by means of the resume interrupt.
When the host controller is selected, no resume interrupt is generated. Use the BCHG interrupt to detect a change in the
USB bus state.
32.3.3.9
OVRCR Interrupt
An OVRCR interrupt is generated when the USB0_OVRCURA or USB0_OVRCURB pin level has changed. The levels
of the USB0_OVRCURA and USB0_OVRCURB pins can be checked with the SYSSTS0.OVCMON[1:0] bits. The
external power supply IC can check whether overcurrent has been detected using the OVRCR interrupt.
For OTG connection, whether a change has been detected in the VBUS comparator can be checked using the OVRCR
interrupt.
32.3.3.10
BCHG Interrupt
A BCHG interrupt is generated when the USB bus state has changed. The BCHG interrupt can be used to detect whether
the peripheral device is connected and can also be used to detect a remote wakeup when the host controller is selected.
The BCHG interrupt is generated regardless of whether the host controller or function controller is selected.
32.3.3.11
DTCH Interrupt
A DTCH interrupt is generated when disconnection of the USB bus is detected while the host controller is selected. The
USB detects bus disconnection based on USB Specification 2.0.
After detecting a DTCH interrupt, the USB controls hardware as described below (irrespective of the value set in the
corresponding interrupt enable bit). All pipes in which communications are currently carried out for the pertinent port
should be terminated by software and make a transition to the wait state for bus connection to the pertinent port (wait
state for ATTCH interrupt generation).
Modifies the DVSTCTR0.UACT bit for the port in which a DTCH interrupt has been detected to 0.
Puts the port in which a DTCH interrupt has been generated into the idle state.