DisplayPort

DisplayPort

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Type - Digital audio/video connector

Production history

Designer - VESA

Designed - 2006-2007

Produced - 2008 expected

Specifications

Hot pluggable - Yes

External - Yes

Electrical - +3.3V

Max voltage - 16.0 V

Max current - 500mA

Audio signal - Optional, maximum 8-channel uncompressed 192 kHz, 24-bit audio, 6.144 Mbit/s bitrate

Video signal - Optional, maximum 2560x1600 resolution

Data signal - Yes

Bandwidth - 1.62 or 2.7 Gbit/s per lane (total 6.48 Gbit/s or 10.8 Gbit/s) plus 1 Mbit/s for AUX CH (for additional data)

Protocol - mini-packet

Cable - maximum length 15 meters (video transmission of resolution 1080p at 24bpp, 50/60 Hz), 3 meters for full bandwidth transmission, made of materials of either copper or optical fibre

Pins - 20 (external connectors)/32 (internal connector for notebooks)

Pin out

Array

External connector (source-side) on PCB

Pin 1 - ML_Lane 0(p) - ‘True’ Signal for Lane 0

Pin 2 - GND - Ground

Pin 3 - ML_Lane 0(n) - ‘Complement’ Signal for Lane 0

Pin 4 - ML_Lane 1(p) - ‘True’ Signal for Lane 1

Pin 5 - GND - Ground

Pin 6 - ML_Lane 1(n) - ‘Complement’ Signal for Lane 1

Pin 7 - ML_Lane 2(p) - ‘True’ Signal for Lane 2

Pin 8 - GND - Ground

Pin 9 - ML_Lane 2(n) - ‘Complement’ Signal for Lane 2

Pin 10 - ML_Lane 3(p) - ‘True’ Signal for Lane 3

Pin 11 - GND - Ground

Pin 12 - ML_Lane 3(n) - ‘Complement’ Signal for Lane 3

Pin 13 - GND - Ground

Pin 14 - GND - Ground

Pin 15 - AUX_CH(p) - ‘True’ Signal for Auxiliary Channel

Pin 16 - GND - Ground

Pin 17 - AUX_CH(n) - ‘Complement’ Signal for Auxiliary Channel

Pin 18 - Hot Plug - Hot Plug Detect

Pin 19 - DP_PWR Return - Connector Power return

Pin 20 - DP_PWR - Power for connector

1) Pins 13 and 14 may either be directly connected to ground or connected to ground through a pulldown device.

2) This is the pinout for source-side connector, the sink-side connector pinout will have lanes 0-3 reversed in order, i.e. lane 3 will be on pin 1 and 3 while lane 0 will be on pin 10 and 12.

DisplayPort is a digital display interface standard (approved May 2006, current version 1.1 approved on April 2, 2007) put forth by the Video Electronics Standards Association (VESA). It defines a new license-free, royalty-free, state-of-the-art digital audio/video interconnect, intended to be used primarily between a computer and its display monitor, or a computer and a home-theater system.

 

Overview

The DisplayPort connector supports 1 to 4 data pairs in a Main Link that also carries audio and clock signals, each with a transfer rate of 1.62 or 2.7 gigabits per second (Gbit/s). The Video signal path supports 6 to 16 bits per color channel. A bi-directional auxiliary channel runs at a constant 1 megabit per second, and serves as Main Link management and device control using VESA EDID and VESA MCCS standards. The Video signal is not compatible with DVI or HDMI, but the specification will allow pass-through of these signals. DisplayPort supports embedded clock, unlike DVI/HDMI which require a separate clock pair. The data transmission protocol in DisplayPort is Micro-Packet based which is extensible in future to add features, whereas DVI/HDMI transmission protocol is Serial Data Stream at 10x pixel clock rate. However one of the biggest advantage that DisplayPort provides over DVI/HDMI is that DisplayPort is intended to consolidate both external(box-to-box) and internal (LCD panel) display connections.

DisplayPort supports a maximum of 10.8 Gbit/s data rate and WQXGA (2560×1600) resolution over a 3 meter cable.^[1]

DisplayPort includes optional DPCP (DisplayPort Content Protection) copy-protection from AMD, which uses 128-bit AES encryption, with modern cryptography ciphers. It also features full authentication and session key establishment (each encryption session is independent). There is an independent revocation system. This portion of the standard is licensed separately. It also adds support for verifying the proximity of the receiver and transmitter, a technique intended to ensure users are not bypassing content protection system to send data out to distant, unauthorized users.

DisplayPort is a competitor to the HDMI connector (with HDCP copy-protection), the de facto digital connection for high-definition consumer electronics devices. Another competitor is Unified Display Interface,^[2] a low cost compatible alternative to HDMI and DVI. However, the main supporter of UDI, Intel, has stopped the development of the technology and now supports DisplayPort.

Newly featured in version 1.1 is the support of HDCP content protection and support for fiber optic cables as an alternative to copper, allowing a much longer reach between source and display without image degradation.^[3] Revision 2.0 is planned for later release.

Before being acquired by AMD, one of the supporters, ATI reported that they were expecting DisplayPort products in early 2007. The AMD/ATI merger completed July 2006 might have postponed the availability of DisplayPort products somewhat, but it seems as though AMD has decided to use DisplayPort as the standard port for its Fusion processor platform, and upcoming mobile platforms after 2008 as AMD announced that they will introduce their first DisplayPort products in late 2007 as a part of their forthcoming platforms for mainstream on December 15, 2006.

On July 25, 2007, at AMD's Technology Analyst Day 2007, AMD renewed their commitment to supporting DisplayPort with upcoming RS780 chipset and RV670 graphics cards with external DisplayPort transmitter. The company also committed to implement the transmitter on chip level for its RV635 and RV620 graphics products in its Financial Analyst Day 2007 held on December 13, 2007, providing support without external transmitters.

Genesis Microchip also announced DisplayPort products to be available in 2007^[4], as did Samsung^[5]. A concept monitor by Dell implementing DisplayPort was demonstrated early May 2007.^[6]

The new Dell 3008WFP 30-inch and upcoming 2408WFP 24-inch monitors released in January 2008 both support the DisplayPort. ^[7]

Supporters

There are several companies stated to support DisplayPort: Luxtera, AMD, Intel, Dell, Genesis Microchip, Hewlett-Packard, Lenovo, Hosiden Corporation, Molex, NVIDIA, Philips, Samsung, Parade Technologies, Analogix, Quantum Data, and Tyco Electronics.

Advantages

1. Based on micro-packet protocol
   • Allows easy expansion of the standard
   • Allows multiple video streams over single physical connection (in a future version)
2. Designed to support internal chip-to-chip communication
   • Can drive display panels directly, eliminating control circuits and allowing for cheaper and slimmer displays
   • Aimed to replace internal LVDS links in notebook panels with a unified link interface
3. Allows backward compatibility with single link DVI/HDMI; dual link DVI/HDMI and analog VGA require active convertor adapters or dongles
4. Supports both RGB and YCbCr color spaces (ITU-R BT.601 and BT.709 format)
5. Auxiliary channel can be used for touch-panel data, USB links, camera, microphone, etc.
6. Fewer lanes with embedded clock reduce RFI.

Compliance testing

VESA has selected four internationally-known organizations ? Allion Test Lab, Inc., Contech Research, ETC, and NTS for compliance testing with emerging DisplayPort standard. In September, 2007, the version 1.0 of the standards for PHY layer and link layer compliance testing has been released and hosted on VESA website for public download.

Technical specifications

• 10.8 Gbit/s forward link channel supports high resolution monitors up to 2560×1600 with single cable.^†
• 8B/10B data transmission
• Open and extensible standard to help with broad adoption.
• Supports color depth of 6, 8, 10, 12 and 16 bits per component.
• Full bandwidth transmission for 3 meter cable.
• Reduced bandwidth transmission, 1080p, for 15 meter cable.
• DisplayPort connector assists in blind connection by just feeling.
• 128-bit AES DisplayPort Content Protection (DPCP) support, and support for 40-bit High-bandwidth Digital Content Protection (HDCP) from version 1.1 onwards.
• Supports internal and external connections so that one standard can be used by computer makers reducing costs.^[8]

The specifications can be downloaded at DisplayPort.org with free registration.^[9]

† 70fps × 30bpp (RGB) × 2560 × 1600 = 7.4 Gbit/s, 60fps × 36bpp (YCbCr 4:4:4) × 1920× 1080 = 4.5 Gbit/s, not taking into account blanking.

See also

• List of display interfaces

References

1. ^ Thomas Ricker (2007-01-03). DisplayPort to support HDCP, too. Engadget. Retrieved on 2007-12-22.
2. ^ Tuan Nguyen (2007-02-19). The Future of HDMI. DailyTech. Retrieved on 2007-07-16.
3. ^ VESA Enables Optical Video Interconnect in DisplayPort Standard (Press Release). Luxtera Inc. (2007-04-17). Retrieved on 2007-07-16.
4. ^ Genesis Microchip (GNSS) Q4 2006 Earnings Conference Call. Seeking Alpha (2006-05-02). Retrieved on 2007-07-16.
5. ^ Samsung touts development of first DisplayPort desktop LCD. TG Daily (2006-07-25). Retrieved on 2007-07-25.
6. ^ Dell Shows Off Super-Slim Display Port LCD Monitor. Gearlog.com (2007-05-17). Retrieved on 2007-07-16.
7. ^ Dell 3008WFP specifications, retrieved January 30, 2008
8. ^ http://www.audioholics.com/education/display-formats-technology/vesa-displayport-standard-v1.0/displayportdvihdmicompared.gif
9. ^ http://www.displayport.org/technical/ Click on Set -> Download DisplayPort Standard