July 2004
AS91L1006BU
6-Port JTAG Gateway
Description
The AS91L1006BU is a one to 6-port
control. Partitioning the IEEE1149.1 chains on the
JTAG gateway. It partitions a single JTAG chain
into six separate chains. These separate chains
can be optionally configured to operate as a single
chain.
PCB has several benefits which include easier
fault diagnostics capabilities as a fault on one of
the IEEE1149.1 Local Scan Ports (LSPs) does
not render the PCB untestable, faster flash
programming on the PCBs, and removal of
IEEE1149.1 signal loading issues.
The AS91L1006BU device is used to
provide enhanced capabilities to the standard
IEEE1149.1. It enables the IEEE1149.1 interface
to be used in a true Multi-Drop environment without
any additional signals. This Multi-Drop capability
enables the standard IEEE1149.1 interface to be
used not just for stand alone PCB (Printed Circuit
Board) testing, but also for complete system
testing including all PCBs within a system back
plane environment.
All of the protocols required for
addressing the AS91L1006BU device via the
Multi-Drop capability and the protocols for
configuring which of the six IEEE1149.1 LSPs on
the AS91L1006BU are to be used, is handled via
3rd party ATPG tools from vendors like Asset-
Intertech and JTAG Technologies. In a Multi-Drop
environment it is also possible to perform
interconnect tests between multiple PCBs within a
system thus extending the interconnect tests to
the back plane itself.
The AS91L1006BU provides the capability
of partitioning the PCB, into multiple smaller
IEEE1149.1 scan chains totally under software
Key Features
ꢀDevice Multi-Drop addressable via the IEEE ꢀProvides the ability to initiate Self-Test on a
1149.1 protocol
remote PCB via a standard IEEE 1149.1
command
ꢀSupport for 6 local scan chains addressable via
the IEEE 1149.1 interface
ꢀSupport for JTAG Technologies AutoWR™
feature
ꢀSupport for Pass-Through™
ꢀPinout and feature set compatible (complete
second source) with the Firecron JTS06BU
device
ꢀSupport for the IEEE 1149.1 USERCODE
instruction
ꢀSupport for Status instruction enabling non-
intrusive monitoring of the system card
ꢀAvailable in a 100-pin LQFP or a 100-pin
FPBGA lead free package
ꢀLocal Scan Port (LSP) enable signal provides the
ability to use non IEEE 1149.1 compliant devices
that require JTAG enable signal
Device Block Diagram
P a s s T h ro u g h E n a b le
P rim a ry 1 1 4 9 .1
J T A G In te rfa c e
L S P 1
L S P 2
S ta tu s D a ta
1 1 4 9 .1 T A P C o n tro lle r
U s e rc o d e
a n d
P a s s T h ro u g h
L S P 3
D a ta
L o g ic
& L o c a l
B o u n d a ry R e g is te r S e le c tio n L o g ic
S c a n P o rt
C o n n e c tio n /
C o n fig
L S P 4
L S P 5
L S P 6
lo g ic
D e v ic e
a d d re s s
D e v ic e
S e le c tio n
L o g ic
L o c a l S c a n P o rt
P a rk /U n -p a rk
S y n c L o g ic
Figure 1 - AS91L1006BU Device Block Diagram
Alliance Semiconductor
2575 Augustine Drive • Santa Clara, CA 95054 • T: 408-855-4900 • F: 408-855-4999 • www.alsc.com