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ScanExpress Features
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Concurrent (gang) testing and in-system
programming of CPLDs and Flash devices for up to
8,192 boards
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User programmable sustained Test Clock (TCK)
up to 80 MHz, in <2% increment per TAP, at
effective throughput of 80 GHz
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Hardware comparison of expected patterns
against observed results is done concurrently
for each TAP
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Pre-power up test for shorts between power and
ground lines on the UUT for each TAP
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TAP signals and GPIO discrete signals are
individually programmable from 1.3V to 3.3V (5
volt tolerant)
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Direct Write signal for expediting Flash
programming
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Support for monitoring Flash RDY/BSY
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Up to 30 feet of extended distance from the PC
to the Pod, no TAP extenders are needed
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Automatic signal delay compensation for long
cable lengths to the UUT
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32-bit PCI bus interface supports high data
transfer rates
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16 bits of programmable parallel I/Os
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Plug and Play drivers for Windows
98/NT/2000/XP/Vista
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Scalable architecture allows expansion of the
system at incremental cost
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Fully compatible with ScanPlus family of
product
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Hardware Based Parallel Operations
ScanExpress is based on special hardware
that autonomously performs concurrent (gang) testing and
programming of multiple units without software
intervention. The entire testing and programming,
including on-the-fly verification of results, is done in
modular and expandable hardware.
Modular Hardware
The major hardware elements of this system include:
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PCI-1149.1/Turbo™ or
NetUSB-1149.1/E™ or NetUSB-1149.1/SE™ or CPXI-1149.1/Turbo™ boundary-scan controller
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ScanTAP-4 remote intelligent pod
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ScanTAP-8 remote intelligent pod
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ScanTAP-32 remote intelligent pod
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ScanHUB-16 boundary-scan
expansion ports
The PCI-1149.1/Turbo™ boundary-scan
controller card is the key element of the ScanExpress
system. The PCI-1149.1/Turbo contains several
performance enhancing functional sections aimed at
increasing test vector and in-system programming
throughput. The combination of these functional elements
results in a very high data-scanning rate, which is
completely decoupled from the PCI bus and the host
computer.
The scan patterns, generated by the
PCI-1149.1/Turbo controller, are then distributed to the
target system either directly through the ScanTAP‑4 and
ScanTAP-32 pods or via the ScanHUB-16. The ScanTAP-4 and
ScanTAP-32 pods can apply test vectors and/or ISP
patterns to target boards with a variety of JTAG chain
topologies. In the simplest, yet often used case, the
ScanTAP-4, ScanTAP-8, and ScanTAP-32 will provide the interface
between the PCI-1149.1/Turbo controller and a target
system consisting of a single JTAG Test Access Port
(TAP). This would be the case where the target system
consists of one JTAG chain and its single associated
TAP.
If the board under test consists of
groups that include multiple devices, each with their
own respective TAP, then the ScanTAP-4, ScanTAP-8, and ScanTAP-32
allow for test vectors to be applied to each of the
target TAPs individually, one TAP at a time, or jointly
to all of the TAPs.
Note that the concept of concurrency here
not only applies to the simultaneous application of test
vectors and ISP patterns to each board but also applies
to the simultaneous verification of each individual
board. A failure on any of the individual boards will
be properly logged and will not prohibit the
continuation of testing on the remaining boards. The
concurrent or gang mode of operation offers great
performance increases when testing, in-system
programming, and verifying multiple targets.
To accommodate for nearly unlimited
scalability, Corelis provides the ScanHUB-16. Just like
a network hub that fans a server’s network connection to
multiple clients on the LAN, the ScanHUB-16 fans out the
PCI-1149.1/Turbo controller interface to multiple
ScanTAP intelligent pods. The ScanHUB-16 connects the
host boundary-scan controller to up to 16 ScanTAP
intelligent pods, such as the ScanTAP-4 or ScanTAP-32.
As an example, a ScanHUB-16 with 16 ScanTAP-32
intelligent pods will enable the simultaneous testing
and programming of up to 512 Target TAPs.
To further expand a system’s TAP scanning
capability, the user can connect a second tier of
ScanHUB-16 hubs to the expansion ports of the primary
hub. This configuration fans out the controller to up
to 256 (16×16) ScanTAP intelligent pods. Since each
ScanTAP-32 pod can drive up to 32 TAPs, which enables
the concurrent scanning of up to 8192 TAPs in total.
ScanExpress Runner
ScanExpress Runner™ software is a
powerful, yet easy to use Test Executive that allows
parallel testing and in-system programming up to 8,192
boards. An intuitive Graphical User Interface (GUI)
allows the user to configure the ScanExpress Runner
system to support practically any target configuration
and JTAG chain topology.
ScanExpress Runner software then applies
Boundary-Scan Test and ISP patterns to a Unit Under Test
(UUT), reads back the responses, and provides
comprehensive fault detection and isolation of the
Boundary-Scan chain infrastructure, board interconnect,
buswire, pullup/pulldown resistors, and clusters such as
CPLDs, memories, FIFOs and other failures.
Programmable Clock
The system-wide TCK rate for all TAP
ports is programmable under software control. A wide
range of TCK frequencies can be achieved by using the
on-board Phase-Locked-Loop (PLL) generation circuitry.
The user is given the ability to select the desired TCK
rate from a range of values up to 80 MHz at resolution
increments of less than 2%. Should an external TCK
timing reference be required for synchronization, or a
user-unique frequency, an external SMB connector is
provided.
Adjustable Low Voltage Outputs
The voltage level of the parallel I/O,
the local TAP port, and each pod TAP is software
programmable and can be set to any voltage between 1.3V
and 3.3V (5V tolerant) in increments of 0.05V. The
ports of the ScanTAP-4, ScanTAP-8, and ScanTAP-32 pods can also be
slew rate (fast/slow) adjusted.
Scan Input Signal Delay Compensation
Automatic delay compensation is inserted
within the signal paths. This feature solves the
well-known problems associated with the combination of
high TCK rates and remote target locations at extended
distances.
Target Voltage Detection System
The Controller and its remote pod include
analog-to-digital converters, which can measure
connected power voltages from the target. Such voltages
from two distinct target levels can be measured and
compared against user-defined limits. This feature can
provide detailed signal voltage checks at any stage of a
test plan.
Automatic Detection of UUT Power Shorts
With the target powered down, a
well-regulated drive current with current limit can be
momentarily applied to the target power bus. By
measuring this current, the approximate load resistance
can be calculated. This provides for the automatic
detection of target power shorts, prior to applying
power to the target unit.
Target Presence Detection Capabilities
The TAPs on the remote pod have a
dedicated pin on the JTAG interface connector that can
be used to detect the presence of the target board. The
state of this signal can be monitored by software to
detect both the presence of the target device as well as
the proper insertion of the test cable.
Support for Third Party Test Executives
ScanExpress Runner is capable of
executing boundary-scan tests and various In-System
Programming (ISP) files from third party applications
using DLLs or command line interface. Drivers for the
popular National Instruments LabWindows/CVI, LabView,
Agilent VEE test environments are provided.
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