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The HDMI 1.3 specification is
available now. CE manufacturers may begin designing products
incorporating the HDMI standard-addressing consumer demand for
HD programming and for DTVs that display this content.
HDMI devices are manufactured to
adhere to various versions of the specification, where each
version is given a number such as 1.0, 1.2, or 1.3a. Each
subsequent version of the specification uses the same kind of
cable but increases the bandwidth and/or capabilities of what
can be transmitted over the cable.For example the previous
maximum pixel clock rate of HDMI interface was 165 MHz which was
sufficient for supporting 1080p at 60 Hz and WUXGA (1920x1200)
at 60 Hz. HDMI 1.3 increased that to 340 MHz which allows for
higher resolution, such as WQXGA (2560x1600), across a single
digital link.
Many people are worried, when
buying HDMI cable, about the spec version of the cable in
question. Is it the latest spec version? Will it support all the
features of the devices it's hooked to? Most of the fears and
doubts associated with this question are unfounded, but there
are some interesting issues with regard to HDMI spec version,
and we'll sort those out here.
What Are The Specific
Versions?
There have been been five versions of the principal HDMI spec
document till now. Additionally, however, some references to
specs are not to the principal HDMI spec document, but to the
"Compliance Testing Specification" document, and there have been
six versions of that document. The versions of the two, to date,
are:
* HDMI Specifications:
o HDMI Specification 1.1
o HDMI Specification 1.2
o HDMI Specification 1.2a
o HDMI Specification 1.3
o HDMI Specification 1.3a
* HDMI Compliance Testing Specifications:
o Compliance Test Specification 1.1
o Compliance Test Specification 1.2a
o Compliance Test Specification 1.3a
o Compliance Test Specification 1.3b
o Compliance Test Specification 1.3b1
o Compliance Test Specification 1.3c
The HDMI Licensing authority allows anyone to download a copy of
the current version of the main HDMI spec document from its site
at hdmi.org. For some reason, however, HDMI, LLC does not
authorize release of the Compliance Test Specification to the
general public. That's unfortunate, because it's in the CTS that
the details of compliance testing are contained, and there can
be some significance to that.
There is some room for confusion here. We are sometimes asked
whether our cable is 1.3a or 1.3b compliant. As you can see, the
current main spec version is 1.3a, and there is no 1.3b. But the
Compliance Test Spec does have a 1.3b version, as well as a 1.3c
version (testing for cables was unaffected by these minor CTS
revisions, except that 1.3c adds new criteria for "active"
cables). Our Belden HDMI cables have been tested under main spec
version 1.3a, CTS version 1.3b (and, in the case of our Series-1
Category 1 approval, CTS version 1.3b1). |
