Texas Instruments OMAP5912 Reference Manual page 1321

Table 3. HC Operating Mode Register (HCCONTROL)(Continued)
Bit Name
3 IE
2 PLE
1:0 CBSR
SPRU761A
Value Description
0 Control ED list is not processed in the next 1-ms frame.
Host controller driver can modify the control ED list. If
driver removes the ED pointed to by the
HCCONTROLCURRENTED from the ED list, it must
update HCCONTROLCURRENTED to point to an ED
still on the list before it re-enables the control list.
1 Enables processing of the control ED list.
HCCONTROLHEADED must be 0 or point to a valid
ED before setting this bit. HCCONTROLCURRENTED
must be 0 or point to a valid ED before setting this bit.
Isochronous enable
0 Isochronous EDs are not processed. The USB host
controller checks this bit every time it finds an
isochronous ED in the periodic list.
When this bit is written to 1, processing of isochronous
EDs can be enabled in the next frame, if not in the
current frame.
1 Enables processing of isochronous EDs
Periodic list enable
0 The periodic ED lists are not processed. When written
to 0, periodic list processing is disabled beginning with
the next frame.
1 Enables processing of the periodic ED lists. When
written to 1, periodic list processing begins in the next
frame.
Control/bulk service ratio
Specifies the ratio between control and bulk EDs
processed in a frame
00 One control ED per bulk ED
01 Two control EDs per bulk ED
10 Three control EDs per bulk ED
11 Four control EDs per bulk ED
The HC command and status register shows the current state of the host
controller and accepts commands from the host controller driver.
USB Host Controller
Type
R/W
R/W
R/W
Universal Serial Bus (USB)
Reset
0
0
00
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