
Functional Description
2-12
Copyright © 2007, 2008 ARM Limited. All rights reserved.
ARM DDI 0402B
Note
nRESET
of the cache controller must be HIGH in MBIST test mode.
The following signals have additional information:
SE
Preservation of array state is required when performing multiload ATPG
runs or when performing
IDDQ
testing. After performing MBIST tests
to initialize the arrays to a required background, the
Automatic Test
Pattern Generator
(ATPG) test procedures must assert
SE
during all test
setup cycles in addition to load/unload. Any clocking during
IDDQ
capture cycles must have array chip select signals constrained.
MBISTRESULT[2:0]
During tests, the
MBISTRESULT[1]
signal indicates failures. You can
operate using two modes, by configuring bit 5 of the engine control
section of the instruction register. If bit 5 is set, the
MBISTRESULT[1]
signal is asserted for a single cycle for each failed compare. If bit 5 is not
set, the
MBISTRESULT[1]
signal is sticky, and is asserted from the first
failure until the end of the test.
At the completion of the test, the
MBISTRESULT[2]
signal goes HIGH.
The
MBISTRESULT[0]
signal indicates that an address expire has
occurred and enables you to measure sequential progress through the test
algorithms.
a. Must be LOW in functional mode.