USB Host Controller
1544
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Universal Serial Bus (USB)
29.2.4.8 HC Current Periodic Register (HCPERIODCURRENTED)
The HC current periodic register defines the physical address of the next endpoint descriptor (ED) on the
periodic ED List.
Figure 29-8. HC Current Periodic Register (HCPERIODCURRENTED) [address = FCF78B1Ch]
31
16
PCED
R-0
15
4
3
0
PCED
Reserved
R-0
R-0
LEGEND: R = Read only; -
n
= value at reset
Table 29-10. HC Current Periodic Register (HCPERIODCURRENTED) Bit Field Descriptions
Bit
Field
Value
Description
31-4
PCED
0-FFF FFFFh
Physical address of current ED on the periodic ED list.
This field represents bits 31:4 of the physical address of the next ED on the periodic ED List.
EDs are assumed to begin at 16-byte-aligned address, so bits 3:0 of this pointer are
assumed to be 0. See
for the restrictions on physical addresses.
3-0
Reserved
0
Reserved
29.2.4.9 HC Head Control Register (HCCONTROLHEADED)
The HC head control register defines the physical address of the head ED of the control ED list.
Figure 29-9. HC Head Control Register (HCCONTROLHEADED) [address = FCF78B20h]
31
16
CHED
R/W-0
15
4
3
0
CHED
Reserved
R/W-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value at reset
Table 29-11. HC Head Control Register (HCCONTROLHEADED) Bit Field Descriptions
Bit
Field
Value
Description
31-4
CHED
0-FFF FFFFh
Physical address of current ED on the periodic ED list.
This field represents bits 31:4 of the physical address of the next ED on the periodic ED List.
EDs are assumed to begin at 16-byte-aligned address, so bits 3:0 of this pointer are
assumed to be 0. See
for the restrictions on physical addresses.
3-0
Reserved
0
Reserved