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Universal Serial Bus Interface – On-The-Go Module
Freescale Semiconductor
10-5
•
Doze — The processor stops the system clocks to the USB OTG module, but the 60 MHz
transceiver clock remains active. In doze mode, detection of resume signaling initiates a restart of
the module clocks.
10.2
External Signal Description
describes the external signal functionality of the USB OTG module.
NOTE
The ULPI signals are multiplexed with the FEC module. This section
describes the signal functions when in ULPI mode; refer to
for more details.
Table 10-2. USB OTG Signal Descriptions
Signal
I/O
Description
On-chip FS/LS transceiver
USB_CLKIN
I
Optional 60 MHz clock source. This signal is also used for the input clock from a ULPI PHY.
USB_DM
I/O Data minus. Output of dual-speed transceiver for the USB OTG module.
State
Meaning
Asserted—Data 1
Negated—Data 0
Timing
Asynchronous
USB_DP
I/O Data plus. Output of dual-speed transceiver for the USB OTG module.
State
Meaning
Asserted—Data 1
Negated—Data 0
Timing
Asynchronous
USB_PULLUP
O
Enables an external pull-up on the USB_DP line. This signal is controlled by the
UOCSR[BVLD] bit.
State
Meaning
Asserted—Pull-up enabled. UOCSR[BVLD] set.
Negated—Pull-up disabled. UOCSR[BVLD] cleared.
Timing
Asynchronous
ULPI Interface
ULPI_DIR
I
Direction. ULPI_DIR controls data bus direction. When PHY has data to transfer to USB port,
it drives ULPI_DIR high to take ownership of the bus. When the PHY has no data to transfer,
it drives ULPI_DIR low and monitors the bus for link activity. The PHY pulls ULPI_DIR high
when the interface cannot accept data from the link. For example, when PHY’s PLL is not
stable.
State
Meaning
Asserted—PHY has data to transfer to the link.
Negated—PHY has no data to transfer.
Timing
Synchronous to USB_CLKIN or ULPI_CLK.
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...