SM CODE SWPMI_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
Table 136. SWPMI_SM_1
SM CODE SWPMI_SM_1
Description Protocol error signals and information redundancy including hardware CRC
Ownership ST
Detailed implementation
SWPMI communication is based on a frame handling concept, composed by a combination
of hardware synchronization signals, frame structure composition, hardware-computed CRC
filed. This mechanism, mainly implemented to manage on-field communication disturbance, is
able to achieve a relevant diagnostic coverage on several SWMPI module failure modes.
Error reporting Error conditions are reported by flag bits in related registers.
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
Direct test procedure for CRC efficiency is not available. CRC run-time hardware failures
leading to disabling such protection fall into multiple-fault scenario, from IEC61508
perspective. Related failures are adequately mitigated by the combination of safety
mechanisms reported in this table, field Multiple-fault protection.
Multiple-fault protection
SWPMI_SM_0: Periodic read-back of configuration registers
SWPMI_SM_2: SWMPI loopback test
Recommendations and known limitations
This method is unable to address all IEC 61508 failure modes related to time handshake
between parties (e.g. resequencing, repetition), leading to the introduction of SWPMI_SM_3.
Enabling related interrupt generation on the detection of errors is highly recommended.
Table 137. SWPMI_SM_2
SM CODE SWPMI_SM_2
Description SWMPI loopback test
Ownership End user
Detailed implementation
By using the SWPMI module loopback function, it is possible to emulate the sending of SWPI
frames and cross-checking the expected result in reception.
Error reporting Error conditions are reported by flag bits in related registers
Fault detection time Depends on implementation
Addressed fault model Permanent
Dependency on Device configuration None
Initialization Loopback mode must be enabled.
UM2305
Hardware and software diagnostics
UM2305 - Rev 10
page 76/110
To Next Page
Loading...
Need help?
General
