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Specification of RAM Test
AUTOSAR CP R20-11
15 of 89 Document ID 76: AUTOSAR_SWS_RAMTest
RamTstNumberOfTestedCells
The RamTstNumberOfTestedCells default is set by configuration (pre-compile or link)
in the RamTstAlgParams container and applies to every block defined within an
algorithm, but can be different for each RamTstAlgParams, thus can be different for
different algorithms or for different parameter sets for the same algorithm.
RamTstNumberOfTestedCells can be changed during runtime using the API
RamTst_ChangeNumberOfTestedCells. This capability, for example, could be used
to reduce the duration of the RAM test task before running some other high-
bandwidth task in order to prevent task overruns. Such a situation could occur when
unusual conditions in a vehicle cause a normally dormant special algorithm to
become active.
RamTstNumberOfTestedCells is only applicable to background testing.
RamTstNumberOfTestedCells may not exceed RamTstMaxNumberOfTestedCells.
The absolute maximum size of RamTstNumberOfTestedCells for a given
RamTstAlgParams container is defined and documented by the implementer. This
maximum should be equal to the sum of the block sizes as defined by the block
descriptions. The integrator sets RamTstExtNumberOfTestedCells to this absolute
maximum value (pre-compile or link) in the RamTstAlgParams container.
RamTstExtNumberOfTestedCells is not changeable during run time.
The integrator also configures (pre-compile or link) the
RamTstMaxNumberOfTestedCells for each RamTstAlgParams container. The
integrator must carefully select RamTstMaxNumberOfTestedCells such that it puts an
upper limit on the run time of RamTst_MainFunction() in a background task according
to the system needs for throughput. In no case should
RamTstMaxNumberOfTestedCells be set to a value greater than
RamTstExtNumberOfTestedCells. RamTstMaxNumberOfTestedCells is not
changeable during run time.
The minimum value of RamTstNumberOfTestedCells is defined and documented by
the implementer. The minimum should be defined as one cell unless there is some
physical reason for a larger minimum. The integrator configures (pre-compile or link)
the RamTstMinNumberOfTestedCells to be greater than or equal to the minimum
defined by the implementer. RamTstMinNumberOfTestedCells applies to the entire
RAM test module, and not to individual algorithms or parameter sets. It is configured
in the RamTstConfigParams container. RamTstMinNumberOfTestedCells is not
changeable during run time.
The cell size (in terms of bits) is also defined by the implementer and cannot be
changed at integration time, as it should be a fixed value for a given processor.
Therefore the corresponding parameter is specified as a published parameter (see
chapter 10.3).
No matter how many blocks or partial blocks are tested in one
RamTst_MainFunction() scheduled call, test status information must be maintained
for each block separately.