Registers

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3.22 HC Port 1 Status and Control Register (HCRHPORTSTATUS1)

The HC port 1 status and control register (HCRHPORTSTATUS1) reports and controls the state of USB host port 1. HCRHPORTSTATUS1 is shown in Figure 23 and described in Table 23.

Figure 23. HC Port 1 Status and Control Register (HCRHPORTSTATUS1)

31

 

 

 

 

 

21

20

19

18

17

16

 

 

 

Reserved

 

 

 

PRSC

OCIC

PSSC

PESC

CSC

 

 

 

R-0

 

 

 

R/W1C-0

R/W-0

R/W1C-0 R/W1C-0 R/W1C-0

15

 

 

 

 

 

 

10

 

9

8

 

 

 

 

Reserved

 

 

 

LSDA/CPP

PPS/SPP

 

 

 

R-0

 

 

 

 

R/W-0

R/W-1

7

 

 

5

4

3

 

2

 

1

0

 

 

Reserved

 

 

PRS/SPR

POCI/CSS

PSS/SPS

PES/SPE

CCS/CPE

 

R-0

 

 

R/W-0

R/W-0

 

R/W-0

R/W-0

R/W-0

LEGEND: R/W = Read/Write; R = Read only; W1C = Write 1 to clear (writing 0 has no effect); -n= value after reset

 

 

 

Table 23. HC Port 1 Status and Control Register (HCRHPORTSTATUS1) Field Descriptions

Bit

Field

Value

Description

 

 

 

 

 

 

 

 

31-21

Reserved

0

Reserved

 

 

 

 

 

 

 

 

20

PRSC

 

Port 1 reset status change. A write of 1 clears this bit; a write of 0 has no effect.

 

 

 

 

0

Port 1 port reset status bit has not changed.

 

 

 

 

 

 

 

 

1

Port 1 port reset status bit has changed.

 

 

 

 

 

 

19

OCIC

0

Port 1 overcurrent indicator change. Because the device does not provide inputs for signaling

 

 

 

 

external overcurrent indication to the USB host controller, this bit is always 0. Overcurrent

 

 

 

 

monitoring, if required, must be handled through some other mechanism. This bit has no

 

 

 

 

relationship to the OTG controller register bits that relate to VBUS.

 

 

 

 

18

PSSC

 

Port 1 suspend status change. A write of 1 clears this bit; a write of 0 has no effect.

 

 

 

 

0

Port 1 port suspend status has not changed.

 

 

 

 

 

 

 

 

1

Port 1 port suspend status has changed. Suspend status is considered to have changed only after

 

 

 

the resume pulse, low-speed EOP, and 3-ms synchronization delays have been completed.

 

17

PESC

 

Port 1 enable status change. A write of 1 clears this bit; a write of 0 has no effect.

 

 

 

 

0

Port 1 port enable status has not changed.

 

 

 

 

 

 

 

 

1

Port 1 port enable status has changed.

 

 

 

 

 

 

16

CSC

 

Port 1 connect status change. If the DR[1] bit in the HC root hub B register (HCRHDESCRIPTORB)

 

 

 

is set to 1 to indicate a nonremovable USB device on port 1, this bit is set only after a root hub

 

 

 

reset to inform the system that the device is attached. A write of 1 clears this bit; a write of 0 has no

 

 

 

effect.

 

 

 

 

 

 

 

 

 

 

0

Port 1 current connect status has not changed.

 

 

 

 

 

 

 

 

1

Port 1 current connect status has changed due to a connect or disconnect event. If current connect

 

 

 

status is 0 when a set port reset, set port enable, or set port suspend write occurs, then this bit is

 

 

 

set.

 

 

 

 

 

 

 

 

15-10

Reserved

0

Reserved

 

 

 

 

 

 

 

 

9

LSDA/CPP

 

Port 1 low-speed device attached/clear port power. This bit is valid only when port 1 current

 

 

 

 

connect status is 1. The host controller driver can write a 1 to this bit to clear the port 1 port power

 

 

 

status bit; a write of 0 has no effect. The USB host controller does not control external port power

 

 

 

using OHCI mechanisms, so, if required, USB host port power must be controlled through other

 

 

 

means. This bit has no relationship to the OTG controller register bits that relate to VBUS. System

 

 

 

software can update this register to simplify host controller driver and/or OTG driver coding.

 

 

 

0

Full-speed device is attached to port 1.

 

 

 

 

 

 

 

 

1

Low-speed device is attached to port 1.

 

 

 

 

 

 

30

Universal Serial Bus OHCI Host Controller

SPRUFM8–September 2008

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Texas Instruments TMS320C6747 DSP manual HC Port 1 Status and Control Register HCRHPORTSTATUS1