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HDMI Releases 1.2a Spec

by January 12, 2006

HDMI Licensing LLC, the agent responsible for licensing the High-Definition Multimedia Interface (HDMI) specification, today announced the availability of the latest revision of the HDMI specification, version 1.2a.

With the release of HDMI 1.2a, CEC features and command sets and CEC compliance tests are now fully specified. In addition, the Founders have created version 1.2a of the HDMI Compliance Test Specification (CTS), which includes a CEC Supplement. HDMI CTS 1.2a has been updated for technical consistency with HDMI Specification 1.2a as well as to the recently released HDMI Specification 1.2.

Significantly, CTS 1.2a contains additional cable and connector testing and Authorized Testing Center (ATC) submission requirements. Specifically, under CTS 1.2a, the Adopter shall submit for testing to the ATC any new HDMI cable whose length exceeds previously tested cables.

Additionally, HDMI Licensing, LLC will maintain a list of approved connectors. For a device to pass CTS 1.2a testing at an ATC, all connectors on such device must appear on the approved connector list. To add a connector to this list, the vendor must submit to the ATC or HDMI Licensing, LLC full and passing testing results.

"HDMI 1.2a will help enable Adopters to build devices incorporating CEC functionality such as single button remote-control" said Leslie Chard, President of HDMI Licensing, LLC. "Additionally, the updated Compliance Test Specification shows the Founder's commitment to ensuring that HDMI devices will correctly interoperate with one another."

The HDMI 1.2a specification can be downloaded at no cost by visiting www.hdmi.org .

HDMI Spec Revision History

1.2a (2005/12/14)
Changes to CEC supplement (see supplement for details)
Eliminated IOFF and made VOFF normative (4.2.4)
Changed CEC resistance to 5 ohms (4.2.10)
Clarified DVI device discrimination (8.3.3)
Several minor editorial (throughout)

1.2 (2005/08/22)
Removed limitations on Type A connector usage (4.1.2, 6.1)
Required new connector mechanical features, optional in 1.1 (4.1.9)
Required Sink support for future AC-coupled Sources (4.2.5)
Add note regarding maximum ratings of Sink (4.2.5)
Clarified Cable Assembly use of +5V Power (4.2.7)
Removed incorrect testing method for DDC capacitance (4.2.8)
Clarified when separate CEC lines on inputs are allowed (4.2.10)
Add maximum resistance spec for interconnected CEC line (4.2.10)
Remove CEC leakage current limit while in standby (4.2.10)
Relaxed YCBCR output requirement for RGB devices (6.2.3)
Added support for additional video formats (6.3, and 7.3.2, 8.2.1)
Corrected sample rate requirement from 1000 ppm to ±1000 ppm (7.3)
Clarified use of Speaker Allocation Data Block (7.4)
Added support for One Bit audio (7.9, and throughout) - SACD Support Added
Clarified exception for 640x480p (VGA) declaration in EDID (8.3.4)
Loosened requirement for duplicated DTD declarations (8.3.4)
Added recommendation for setting Supports_AI (9.2)
Clarified the behavior of Repeater to Sink with Supports_AI (9.3.2)
Clarified rule for DVD-Audio ACP Packet transmission (9.3.5)
Additional minor editorial (throughout)

1.1 (2004/05/20)
Permitted multi-rate preferred format support on Type A Sinks (4.1.2)
Changed connector mechanical spec (4.1.9)
Changed connector electrical spec (4.1.7)
Removed CEC / +5V Power dependency for Source (4.2.7)
Loosened regulation requirements for +5V Power (4.2.7)
Made HPD voltages consistent with new +5V Power (4.2.9)
Clarified CEC connection requirements (4.2.10)
Restricted CTLx values allowed in non-Preamble periods (5.2.1)
Added new Packet Types (5.3.1)
Clarified InfoFrame Packet requirements (5.3.5)
Added ACP and ISRC Packet definitions and usage (5.3.7, 8.8, 9.3) - DVD-Audio Support Added
Specified recommended handling of non-Subpacket 0 CS blocks (7.1)
Clarified audio sample rate requirements (7.3)
Disallowed Layout 1 2-channel (7.6)
Clarified AVI transmission requirements (8.2.1)
Added extension fields and clarified HDMI VSDB (8.3.2)
Clarified DVI/HDMI device discrimination (8.3.3)
Clarified HPD behavior (8.5)
Clarified EDID values of Physical Addresses (8.7)
Made minor editorial changes (throughout)

1.0 (2002/12/09)
Initial Release

About HDMI Licensing, LLC
HDMI Licensing, LLC, a wholly owned subsidiary of Silicon Image, Inc., is the agent responsible for licensing the HDMI Specification, promoting the HDMI standard and providing education on the benefits of HDMI to retailers and consumers. The HDMI Specification was developed by Sony, Hitachi, Thomson (RCA), Philips, Matsushita (Panasonic), Toshiba and Silicon Image as the digital interface standard for the consumer electronics market. The HDMI specification combines uncompressed high-definition video and multi-channel audio in a single digital interface to provide crystal-clear digital quality over a single cable.

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Clint Deboer was terminated from Audioholics for misconduct on April 4th, 2014. He no longer represents Audioholics in any fashion.

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