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Universal Serial Bus Interface – On-The-Go Module
10-2
Freescale Semiconductor
to draw more than the allocated amount of current, the USB host must disable the port and remove power.
USB VBUS is not provided on-chip. This processor provides pins for control and status to an external IC
capable of managing the VBUS downstream supply.
For OTG operations, external circuitry is required to manage the host negotiation protocol (HNP) and
session request protocol (SRP). External ICs that are capable of providing the OTG VBUS with support
for HNP and SRP, as well as support for programmable pullup and pulldown resistors on the USB DP and
DM lines are available from various manufacturers.
The on-chip FS/LS transceiver also includes a programmable pullup resistor on USB DP. This pullup is
configurable via the CCM. See
Chapter 11, “Chip Configuration Module (CCM),”
for more information.
The primary function of the transceiver is the physical signal conditioning of the external USB DP and
DM cable signals for a USB 2.0 network. Several USB system elements are not supported on the device
as they are available via standard products from various manufacturers.
10.1.2
Block Diagram
shows the USB On-The-Go interface using the on-chip full-speed/low-speed transceiver.
Figure 10-1. USB On-The-Go with on-chip FS/LS Transceiver Interface Block Diagram
illustrates the On-The-Go (OTG) configuration with an off-chip ULPI transceiver. The ULPI
transceiver is an implementation of the HS/FS/LS physical layer which encapsulates the 60+ pin UTMI+
interface using a 12-pin digital interface.
Interr
upt Subsys
tem
I2C
Master
FS/LS
Transceiver
OTG
Control
Status
SCL/SDA
VBUS
USBD_DP
USBD_DM
USB On-The-Go
USB Host
/De
v
/O
TG
Con
trol
ler
Chip
Module
Configuration
Inter
nal Bus
Interrupt
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 ...