Freescale Semiconductor MPC5200B ユーザーズマニュアル

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Host Control (HC) Operational Registers
MPC5200B Users Guide, Rev. 1
Freescale Semiconductor
12-9
12.4.2.4
USB HC Interrupt Status Register —MBAR + 0x100C
This register provides status on various events that cause hardware interrupts. When an event occurs, HC sets the corresponding register bit. 
When a bit is set, a hardware interrupt is generated, if the interrupt is enabled in the HcInterruptEnable register and the MasterInterruptEnable 
bit is set. HCD may clear specific bits in this register by writing 1 to bit positions to be cleared. HCD may not set any of these bits. HC never 
clears the bit.
 
29
BLF
BulkListFilled—bit indicates whether there are Bulk List TDs. HCD sets this bit when it adds 
a TD to a Bulk List ED. When HC begins processing the Bulk List head, it checks BF.
If BLF is 0, HC does not start Bulk List processing.
If BLF is 1, HC starts Bulk List processing and sets BF to 0.
If HC finds a Bulk List TD, HC sets BLF to 1, causing Bulk List processing to continue.
If HC does not find a Bulk List TD and HCD does not set BLF, then BLF remains 0 when 
HC completes processing and Bulk List processing stops.
30
CLF
ControlListFilled—bit indicates whether there are Control List TDs. HCD sets this bit when 
it adds a TD to a Control List ED. When HC begins processing the Control List head, it checks 
CLF.
If CLF is 0, HC does not start Control List processing.
If CF is 1, HC starts Control List processing and sets CLF to 0.
If HC finds a Control List TD, CLF is set to 1, causing Control List processing to continue.
If HC does not find a Control List TD and HCD does not set CLF, then CLF remains 0 
when HC completes processing and Control List processing stops.
31
HCR
HostControllerReset—HCD sets bit to initiate a software reset of HC. Regardless of the HC 
functional state, it moves to the USBSUSPEND state in which most of the operational 
registers are reset except those stated otherwise. For example, HcControl Interrupt Routing 
field and no Host bus access is allowed.
On completion of the reset operation, HC clears this bit. Completion must be within 10ms. 
When set, this bit should not cause a root hub reset and no subsequent reset signaling 
should be asserted to downstream ports.
Table 12-4. USB HC Interrupt Status Register
msb  0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
Rsvd
OC
Reserved
W
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31 lsb
R
Reserved
RHSC
FNO
UE
RD
SF
WDH
SO
W
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bits
Name
Description
0
Reserved
1
OC
OwnershipChange—HC sets this bit when HCD sets the HcCommandStatus 
OwnershipChangeRequest field. This event, when unmasked, always generate an immediate 
System Management Interrupt (SMI).
When the SMI pin is not implemented, the OC bit is tied to 0.
2:24
Reserved
Bits
Name
Description