Intel® IXP42X product line and IXC1100 control plane processors—Universal Serial Bus (USB)
v1.1 Device Controller
Intel® IXP42X Product Line of Network Processors and IXC1100 Control Plane Processor
DM September 2006
482 Order Number: 252480-006US
18.5.1.4 Resume Interrupt Request (RESIR)
The resume interrupt request bit is set if the SRM bit in the UDC control register is
cleared, the UDC is currently in the suspended state, and the USB is driven with
resume signalling.
18.5.1.5 Suspend Interrupt Request (SUSIR)
The suspend interrupt request register is set when the USB remains idle for more than
6 ms. The SUSIR bit retains state so software can determine that the USB is idle. If
SRM is 0, SUSIR being set will not generate an interrupt but status continues to be
updated.
18.5.1.6 Suspend/Resume Interrupt Mask (SRM)
The suspend/resume interrupt mask (SRM) masks or enables the suspend interrupt
request to the interrupt controller. When SRM is 1, the interrupt is masked and the
setting of SUSIR will not generate an interrupt. When SRM is 0, the setting of SUSIR
generates an interrupt when the USB is idle for more than 6 ms.
Programming SRM does not affect the state of SUSIR.
18.5.1.7 Reset Interrupt Request (RSTIR)
The reset interrupt request register is set when the host issues a reset. When the host
issues a reset, the entire UDC is reset. The RSTIR bit retains its state so software can
determine that the design was reset. If REM is 0, RSTIR being set does not generate an
interrupt but status continues to be updated.
18.5.1.8 Reset Interrupt Mask (REM)
The reset interrupt mask (REM) masks or enables the reset interrupt request to the
interrupt controller. When REM is 1, the interrupt is masked and the setting of RSTIR
does not generate an interrupt. When REM is 0, the RSTIR setting generates an
interrupt when the USB host controller issues an UDC reset.
Programming REM does not affect the state of RSTIR.
The UDE bit is cleared to 0, which disables the UDC following a Intel XScale® processor
reset. Writes to reserved bits are ignored and reads return zeros.
Register Name: UDCCR
Hex Offset Address: 0XC800B000 Reset Hex Value: 0x000000A0
Register
Description: Universal Serial Bus Device Controller Control Register
Access: Read/Write and Read-Only
Bits
31 876543210
(Reserved)
REM
RSTIR
SRM
SUSIR
RESIR
RSM
UDA
UDE
X 10100000
Resets (Above)