![Intel IXP45X Скачать руководство пользователя страница 378](http://html1.mh-extra.com/html/intel/ixp45x/ixp45x_developers-manual_2073092378.webp)
Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors—USB 2.0 Host Controller
Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
Developer’s Manual
August 2006
378
Order Number: 306262-004US
9.12.4
FRINDEX
Address:
Base + 14Ch
Default Value: Undefined (free running counter)
Attribute:
Read/Write in host mode
Size:
32 bits
This register is used by the host controller to index the periodic frame list. The register
updates every 125 ms (once each micro-frame). Bits [N: 3] are used to select a
particular entry in the Periodic Frame List during periodic schedule execution. The
number of bits used for the index depends on the size of the frame list as set by system
software in the Frame List Size field in the USBCMD register.
This register must be written as a DWord. Byte writes produce-undefined results. This
register cannot be written unless the Host Controller is in the 'Halted' state as indicated
by the HCHalted bit. A write to this register while the Run/Stop hit is set to a one
produces undefined results. Writes to this register also affect the SOF value.
FRE
Frame List
Rollover
Enable
When this bit is a one, and the Frame List Rollover bit in the USBSTS
register is a one, the host controller will issue an interrupt. The
interrupt is acknowledged by software clearing the Frame List Rollover
bit.
Only used by the host controller.
PCE
Port Change
Detect Enable
When this bit is a one, and the Port Change Detect bit in the USBSTS
register is a one, the host controller will issue an interrupt. The
interrupt is acknowledged by software clearing the Port Change Detect
bit.
UEE
USB Error
Interrupt
Enable
When this bit is a one, and the USBERRINT bit in the USBSTS register
is a one, the host controller will issue an interrupt at the next interrupt
threshold. The interrupt is acknowledged by software clearing the
USBERRINT bit in the USBSTS register.
UE
USB Interrupt
Enable
When this bit is a one, and the USBINT bit in the USBSTS register is a
one, the host controller will issue an interrupt at the next interrupt
threshold. The interrupt is acknowledged by software clearing the
USBINT bit.
Table 136.
USBINTR – USB Interrupt Enable
Field
Interrupt
Source
Description
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
(Reserved)
FRINDEX[13:0]