ST STM32L4 Series, User Manual

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SM CODE CRC_SM_0
Ownership ST
Detailed implementation
The CRC algorithm implemented in this module (CRC-32 Ethernet polynomial: 0x4C11DB7)
offers excellent features in terms of error detection in the message. Therefore permanent and
transient faults affecting
CRC computations are easily detected by any operations using the
module to recompute an expected signature.
Error reporting Depends on implementation
Fault detection time Depends on implementation
Addressed fault model Permanent/transient
Dependency on Device configuration None
Initialization Depends on implementation
Periodicity Continuous
Test for the diagnostic Not applicable
Multiple-fault protection CPU_SM_0: Periodic core self-test software
Recommendations and known limitations None
3.6.16 Flexible static memory controller (FSMC)
Table 65. FSMC_SM_0
SM CODE FSMC_SM_0
Description Control flow monitoring in Application software
Ownership End user
Detailed implementation
If FSMC is used to connect an external memory containing software code to be executed by
the CPU, permanent and transient faults affecting the FSMC memory controller are able to
interfere with the access operation by the CPU, leading to wrong data or instruction fetches. A
strong control flow mechanism linked to a system watchdog is able to detect such failures, in
case they interfere with the expected flow of
Application software .
The implementation of this method is identical to the one reported for CPU_SM_1, refer there
for details.
Error reporting Depends on implementation
Fault detection time Depends on implementation. Higher value is fixed by watchdog timeout interval.
Addressed fault model Permanent/transient
Dependency on Device configuration FSMC interface is available only on selected part numbers.
Initialization Depends on implementation
Periodicity Continuous
Test for the diagnostic Not applicable
Multiple-fault protection CPU_SM_0: Periodic core self-test software
Recommendations and known limitations
This mechanism must only be used if FSMC external memory is used to store executable
programs.
Table 66. FSMC_SM_1
SM CODE FSMC_SM_1
Description Information redundancy on external memory connected to FSMC
Ownership End user
UM2305
Hardware and software diagnostics
UM2305 - Rev 10
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