ST STM32L4 Series, User Manual

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SM CODE FFI_SM_0
Periodicity Startup
Test for the diagnostic Not applicable
Multiple-fault protection FFI_SM_1: Periodic read-back of interference avoidance registers
Recommendations and known limitations None
Table 150. FFI_SM_1
SM CODE FFI_SM_1
Description Periodic read-back of interference avoidance registers
Ownership End user
Detailed implementation
This method contributes to the reduction of the probability of cross-interferences between
peripherals that can potentially conflict on the same input/output pins, including for instance
unused peripherals. This diagnostic measure must be applied to following registers:
•
clock enable and disable registers
• alternate function programming registers
Detailed information on the implementation of this method can be found in
Section 3.6.14 Extended interrupt and events controller (EXTI) .
Error reporting Refer to NVIC_SM_0
Fault detection time Refer to NVIC_SM_0
Addressed fault model Refer to NVIC_SM_0
Dependency on Device configuration Refer to NVIC_SM_0
Initialization Refer to NVIC_SM_0
Periodicity Refer to NVIC_SM_0
Test for the diagnostic Refer to NVIC_SM_0
Multiple-fault protection Refer to NVIC_SM_0
Recommendations and known limitations Refer to NVIC_SM_0
3.7 Conditions of use
The table below provides a summary of the safety concept recommendations reported in Section 3.6 Hardware
and software diagnostics . The conditions of use to be applied to STM32L4 and Series devices
are reported in form of safety mechanism requirements. Exception is represented by some conditions of use
introduced by FMEA analysis in order to correctly address specific failure modes. These conditions of use are
reported at the end of the table presented in this section.
Rank column reports how related safety mechanism has been considered during the analysis, with following
meaning:
M The safety mechanism is always active during normal operation, with no possibility for End user to deactivate it.
++ The safety mechanism is highly recommended as common practice. It is considered in this document for the
computation of safety metrics to allow the use of
Device in systems implementing safety functions up to SIL 2 with
a single MCU or up to SIL 3 with two MCU s in 1oo2 scheme.
+ The safety mechanism is recommended as additional safety measure, but not considered in this document for the
computation of safety metrics. STM32L4 and Series users can skip the implementation in case it is in
contradiction with functional requirements or overlapped by another mechanism ranked
++ .
o The safety mechanism is optional. It is not strictly required for the implementation of safety functions up to SIL 2, or
it is related to a specific MCU configuration.
UM2305
Conditions of use
UM2305 - Rev 10
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