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MCF52211 ColdFire® Integrated Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor
15-1
Chapter 15  
Universal Serial Bus, OTG Capable Controller
NOTE
Portions of 
 
relating to the EHCI specification are Copyright © Intel Corporation 
1999-2001. The EHCI specification is provided “As Is” with no warranties 
whatsoever, including any warranty of merchantability, non-infringement, 
fitness for any particular purpose, or any warranty otherwise arising out of 
any proposal, specification or sample. Intel disclaims all liability, including 
liability for infringement of any proprietary rights, relating to use of 
information in the EHCI specification. Intel may make changes to the EHCI 
specifications at any time, without notice.
This chapter describes the USB Dual Mode FS/LS Host - FS Device Controller and Universal Serial Bus 
(USB) interface, which implements many industry standards. However, it is beyond the scope of this 
document to document the intricacies of these standards. Instead, it is left to the reader to refer to the 
governing specifications.
The following documents are available from the USB Implementers Forum web page at 
:
Universal Serial Bus Specification, Revision 1.1 
On-The-Go Supplement to the USB 2.0 Specification, Revision 1.0a 
15.1
Introduction 
This section describes the USB Dual-Mode (DM) controller. The OTG implementation in this module 
provides limited host functionality as well as device FS solutions for implementing a USB 2.0 
full-speed/low-speed compliant peripheral. The OTG implementation supports the On-The-Go (OTG) 
addendum to the USB 2.0 Specification. Only one protocol can be active at any time. A negotiation 
protocol must be used to switch to a USB host functionality from a USB device. This is known as the 
Master Negotiation Protocol (MNP).
15.1.1
USB 
The USB is a cable bus that supports data exchange between a host computer and a wide range of 
simultaneously accessible peripherals. The attached peripherals share USB bandwidth through a 
host-scheduled, token-based protocol. The bus allows peripherals to be attached, configured, used, and 
detached while the host and other peripherals are in operation.