ULPI registers

STULPI01A - STULPI01B

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Table 21.

USB interrupt enable falling register

Address: 10h-12h (Read), 10h (Write), 11h (Set), 12h (Clear)

(If set, the bits in this register cause an interrupt event notification to be generated when the

corresponding PHY signal changes from high to low. By default, all transitions are enabled. RxActive and

RxError must always be communicated immediately and so are not included in this register. Interrupt

circuitry can be powered down in any mode when both rising and falling edge enables are disabled. To

ensure interrupts are detectable when clock is powered down, the link should enable both rising and

falling edges.)

Field name

Bits

Access

Reset

Description

Host disconnect fall

0

rd/wr/s/c

1b

Generates an interrupt event notification when the host

disconnect changes from high to low. Applicable only in

host mode.

VbusValid fall

1

rd/wr/s/c

1b

Generates an interrupt event notification when

VbusValid changes from high to low.

SessValid fall

2

rd/wr/s/c

1b

Generates an interrupt event notification when

SessValid changes from high to low. SessValid is the

same as UTMI+ AValid.

SessEnd fall

3

rd/wr/s/c

1b

Generates an interrupt event notification when SessEnd

changes from high to low.

ID fall

4

rd/wr/s/c

1b

Generates an interrupt event notification when ID

changes from high to low. ID is valid 50ms after IdPullup

is set to 1b, otherwise ID is undefined and should be

ignored.

Reserved

7:5

rd/wr/s/c

0b

Reserved

Table 22.

USB interrupt status register

Address: 13h (Read-only)

(Indicates the current value of the interrupt source signal. Interrupt circuitry can be powered down in any

mode when both rising and falling edge enables are disabled. To ensure interrupts are detectable when

clock is powered down, the link should enable both rising and falling edges.)

Field name

Bits

Access

Reset

Description

Host disconnect

0rd

0b

Current value of UTMI+ Host disconnect output.

Applicable only in host mode. Automatically reset to 0b

when Low Power Mode is entered.

VbusValid

1

rd

0b

Current value of UTMI+VbusValid output.

SessValid

2rd

0b

Current value of UTMI+SessValid output. SessValid is the

same as UTMI+ AValid.

SessEnd

3

rd

0b

Current value of UTMI+SessEnd output.

ID

4rd

0b

Current value of UTMI+ID output. ID is valid 50ms after

IdPullup is set to 1b, otherwise ID is undefined and should

be ignored.

Reserved

7:5

rd

0b

Reserved