Note that the TUNITCON register field will stop incrementing when it reaches its maximum
value so it will not rollover to zero and start counting up again.
46.5.2 Interrupts and Events
The USBDCD module has an interrupt to alert system software of certain events, which
are listed in the following table. All events except the Phase Complete event for the Data
Pin Detection phase can trigger an interrupt.
Table 46-18. Events Triggering an Interrupt by Sequence Phase
Sequence
Phase
Event
Event Description
Phase
Description
Data Pin
Detection
Phase
Complete
The module has detected data pin contact.
No interrupt occurs: CONTROL[IF] = 0.
ERR = 0
SEQ_STAT = 01
SEQ_RES = 00
TO = 0
Charging Port
Detection
Phase
Complete
The module has completed the process of
identifying if the USB port is a charging port or
not.
ERR = 0
SEQ_STAT = 10
SEQ_RES = 01 or 10
TO = 0
Error
The module cannot identify the type of port
because the D- line is above the USB's VLGC
threshold.
ERR = 1
SEQ_STAT = 10
SEQ_RES = 00
TO = 0
Charger Type
Detection
Phase
Complete
The module has completed the process of
identifying the charger type detection.
Note: The ERR flag always reads as zero
because no known error conditions
are checked during this phase.
ERR = 0
SEQ_STAT = 11
SEQ_RES = 11 or 10
TO = 0
Sequence
Timeout
Error
The timeout interval from the time the USB
device attaches to a USB port until it connects
has elapsed
ERR = 1
TO = 1
1. See the description of the Status Register for register information.
2. The SEQ_STAT and SEQ_RES fields retain the values held at the time of the timeout error.
46.5.2.1 Interrupt Handling
Software can read which event caused the interrupt from the STATUS register during the
interrupt service routine.
Chapter 46 USB Device Charger Detection Module (USBDCD)
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
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