Hello,
according to SM_211 of Safety Manual (Rev.4) , "It is assumed that the Application Fault Tolerant Time Interval is 100 ms."
In our understanding, the implication is that shorter FTTI (t<100ms) can not be guaranteed with this uc - hence the software/application shall have an FTTI > 100ms.
Is this correct or the implication is that 100ms is the upper limit for the application and safety relevant project shall have a t <100ms FTTI?
Thanks and best regards,
L
Solved! Go to Solution.
Hi L,
Please find below the answer:
L: In our understanding, the implication is that shorter FTTI (t<100ms) can not be guaranteed with this uc - hence the software/application shall have an FTTI > 100ms.
MS: The single-point Fault Tolerant Time Interval (FTTI)/Process Safety Time (PST) [Item level] is the time span between a failure that has the potential to give rise to a hazardous event and the time by which counteraction has to be completed to prevent the hazardous event from occurring.
Fault indication time(MCU) is the time from the occurrence of a fault to when the S32K1xx and S32K14xW is switched into a Safe stateMCU.
FTTI is set at item level and not uc level. Fault Indication time is for uc. PFA the image below for better understanding:
L: Is this correct or the implication is that 100ms is the upper limit for the application and safety relevant project shall have a t <100ms FTTI?”
MS: Here FTTI>=100ms. So, 100ms is the lower limit for the application and safety project shall have a t>=100msFTTI.
Thanks and regards,
Manibha Sharma
Hi L,
Please find below the answer:
L: In our understanding, the implication is that shorter FTTI (t<100ms) can not be guaranteed with this uc - hence the software/application shall have an FTTI > 100ms.
MS: The single-point Fault Tolerant Time Interval (FTTI)/Process Safety Time (PST) [Item level] is the time span between a failure that has the potential to give rise to a hazardous event and the time by which counteraction has to be completed to prevent the hazardous event from occurring.
Fault indication time(MCU) is the time from the occurrence of a fault to when the S32K1xx and S32K14xW is switched into a Safe stateMCU.
FTTI is set at item level and not uc level. Fault Indication time is for uc. PFA the image below for better understanding:
L: Is this correct or the implication is that 100ms is the upper limit for the application and safety relevant project shall have a t <100ms FTTI?”
MS: Here FTTI>=100ms. So, 100ms is the lower limit for the application and safety project shall have a t>=100msFTTI.
Thanks and regards,
Manibha Sharma