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VESA DisplayPort Alt Mode Standard Version 2.0
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Section 1: Introduction
Terms, Acronyms, and Abbreviations
1.4 Terms, Acronyms, and Abbreviations
Table 1-1 lists terms, acronyms, and abbreviations that are defined in the USB-related
Specifications referenced in Table 1-5, and are provided here for reference.
Table 1-1: Terms, Acronyms, and Abbreviations Referenced from USB-related
Specifications (Informative)
Term Definition
Accept Message Accept Message. USB PD Message that is used to indicate that the requested action is accepted.
active cable Cable that incorporates signal conditioning logic on the high-speed data path. An active cable
is electronically marked (see electronically marked cable) to differentiate it from a passive cable,
and has signal conditioning characteristics that may be controlled by the DFP_U.
Alternate Mode
or
Alt Mode
Operation defined by a vendor or standards organization that is associated with an SVID
assigned by the USB Implementers Forum, Inc. (USB-IF; see usb.org/members). Entry
to and exit from an Alternate Mode is controlled by the USB PD Structured VDM Enter Mode
and Exit Mode commands.
Note: The Alternate Mode defined by this Standard is DisplayPort Alt Mode.
AMA Alternate Mode Adapter.
Attention Command Attention Command. USB PD command request that is used by the UFP_U to request service
from the DFP_U.
captive cable Cable that is terminated on one end with a USB Type-C plug and has a vendor-specific means
of connection (i.e., hardwired or custom detachable) on the opposite end.
CC Configuration Channel. Used in the discovery, configuration, and management of connections
across a USB Type-C cable.
Contract
(Explicit Power
Contract)
USB PD agreement on both power level and direction that is reached between a Port Pair. May be
explicitly negotiated between the Port Pair (Explicit), –or– an implicit power level that is defined
by the current state (Implicit). In this Standard, refers to a USB PD Explicit Power Contract unless
specifically stated otherwise.
DFP Downstream-Facing Port. Specifically associated with the flow of data in a USB connection.
Typically, the ports on a USB host or the ports on a hub to which devices are connected. In its
initial state, the DFP sources V
BUS
and V
CONN
, and supports data. A charge-only DFP only
sources V
BUS
(see DFP_U in Table 1-2).
direct-attach Indicates that a USB host’s DFP_U is connected directly, either with or without a cable
(e.g., thumb drive), to the device’s UFP_U. (USB-C)
Discover Identity
Command
Discover Identity Command. USB PD command request from an Initiator to identify its Port
Partner and for an Initiator (V
CONN
Source) to identify the Responder (cable plug).
Discover Modes
Command
Discover Modes Command. USB PD command from an Initiator to discover the Alternate Modes
that its Port Partner supports and for an Initiator (V
CONN
Source) to identify the Responder
(cable plug).
Discover SVIDs
Command
Discover SVIDs Command. USB PD command and request set that are used by an Initiator to
discover the USB SID or the Vendor ID that its Port Partner supports, and for an Initiator (V
CONN
Source) to identify the Responder (cable plug).
dock General term used to describe products that provide multi-function capability and/or port
expanding-type functionality when connected to a USB Type-C DP Source device
(e.g., Multi-function cradle dock).
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