USB Device Controller
1641
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Universal Serial Bus (USB)
29.3.26 Summary of USB Device Controller Interrupts
lists the interrupt types by endpoint types.
Table 29-56. USB Device Controller Interrupt Type by Endpoint Type
Interrupt Type
General USB IRQs (VIM channel # 69 by default)
EP-Specific IRQs (Non-ISO
Interrupt on VIM channel # 70 by
default)
SOF ISO
Interrupt on
VIM channel #
68 by default)
Setup
(EP0)
Control
(EP0)
Out
Control
(EP0)
In
Other
Bulk or
InterruptOut
Bulk or
InterruptIn
(Isochronous)
SOF
Transaction ACKed
X
X
X
X
Transaction NAKed
(if enabled)
X
X
X
X
Transaction Stalled
X
X
X
X
Setup
X
SOF
X
Device state
changed
X
RX DMA EOT
(non_ISO)
X
RX DMA trans count
(non_ISO)
X
TX DMA
done
(non_ISO)
X
29.3.26.1 USB Device Controller Clock Control
The device global clock module (GCM) provides a single 48-MHz clock to the USB device controller and
USB host controller. This is the VCLKA3 clock domain. This clock domain can be stopped by software to
reduce USB host and USB device controller power consumption when USB functionality is not needed.
The GCM controls the 48-MHz clock to the USB device controller via the following memory-mapped
registers:
•
SYS.CDDIS
•
SYS.CDDISSET
•
SYS.CDDISCLR
29.3.26.2 USB Device Controller Hardware Reset
Reset of the USB device controller is provided by the SYS module. The system reset signal is used to
reset the USB host controller and the USB device controller. When held in reset, the USB device controller
does not recognize any USB activity, and its registers have no effect on USB functionality.