GE IMP2B 数据表

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GE Intelligent Platforms, a General Electric Company (NYSE: GE), is an experienced high-performance
technology company and a global provider of hardware, software, services, and expertise in automation
and embedded computing. We offer a unique foundation of agile, advanced and ultra-reliable technology
that provides customers a sustainable advantage in the industries they serve, including energy, water,
consumer packaged goods, government and defense, and telecommunications. GE Intelligent Platforms
is a worldwide company headquartered in Charlottesville, VA and is part of GE Home and Business Solutions.
For more information, visit www.ge-ip.com.

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All other brands or names are property of their respective holders.

Specifications are subject to change without notice.

Deployed Test Solutions

tendency towards system upgrades and/
or maintenance in-situ. The opportunity for
human error exists.

GE Intelligent Platform has implemented a
program which does provide an objective
measure of BIT software effectiveness. On
each particular hardware product, a large
number of nodes are chosen randomly,
then each is individually ‘stuck’ high or low
(by connecting to power or ground) on a
real board on which BIT is executed. As the
verification run progresses, each node is
stuck alternately high or low in sequence,
except for nodes which are normally static
high (pulled low), or static low (pulled high).

The equation

n=N/((Nd2/t2P(100-P))+1)

relates the number of tested nodes n,
required within a total number of board
nodes N, to achieve a coverage percent-
age P, with a percentage tolerance d,
and a standard error t. ‘Standard error’
is directly related to the confidence that
the statistical result can be applied to the
whole population of nodes.

For an expected coverage of 95% with
a confidence of 90%, the number of test
nodes required for a typical single board
computer (SBC) of around 5000 nodes is
calculated to be around 165. For such a
board, GE Intelligent Platform executes
a test coverage verification run on these
165 randomly selected board nodes – thus
ascertaining a real, ‘operative’ test coverage.

It is a prime requirement of BIT that it is
able to operate in a deployed system.
In such a system a typical circuit board
assembly would have some or all of its
interfaces connected to external equipment.
On a modern SBC these could include

Ethernet, serial lines, SCSI, IDE, VMEbus,
PCIbus and others. It is clear that a large
fraction of the nodes on such a board are
actually 
connected to offboard electronics of
various types, creating difficulties for any
onboard test firmware designed ideally 
to verify all nodes, whether they go off-
board or not. Loopback paths via which
the firmware may verify these externally
connected nodes will be system- and
application-dependent.

Figure 2 below depicts the areas containing 
edge and internal nodes for a simple,
example portion of SBC circuitry. All nodes
involved in a system loopback path (rather
than an internal loopback path) are termed
‘edge’ nodes. All other nodes (whether
they actually have, in practice, an internal
loopback path or no loopback path at all),
are termed ‘internal’ nodes. The front cover
illustration gives a conceptual representation
of this situation over the whole of a typical SBC.

In order to allow the testing of edge nodes,  
GE Intelligent Platform has provided con-
figurable tests that can verify standard
responses from other system elements
such as VME, Ethernet, serial etc. System

integrators can use such tests as are appli-
cable to their own system configurations,
increasing system coverage without the
need to write custom tests. These ‘edge
node tests’ can also be enabled for Acceptance
Test Procedures, avoiding the need for  
different software within acceptance  
test equipment.

GE Intelligent Platform offers standard
COTS test firmware that has a functionally
verifiable coverage, co-operative with all
other GE Intelligent Platform system elements,
and providing configurable tests for veri-
fication of board nodes leading to third
party or customer proprietary equipment.
We believe no-one offers more.

Detailed information on GE Intelligent Platform’s
verification process is contained in the brochure
‘GE Intelligent Platform BIT Coverage: A
Straightforward Guide’, which is available
from your local sales office. This booklet
includes a summary of market approaches,
equivalence factors, echo testing, headline
and auxiliary coverage, and an example
test verification case for a PowerX board
showing 97% headline coverage.