Safety, Reset-action after uncorrectable ECC error SRAM.

[joakimB]

Hi,
I am currently working with safety-related implementations on a Tc297. I have noticed that the SRAM can be reset/cleared for warm/cold resets but not for application/system-resets. If we would detect an uncorrectable ECC-error on SRAM, let's say the CPU0.DSPR, my plan would be to do a system-reset and continue. However, what I've seen I cannot set any resets that clears the SRAM. The ECC-error would still be there after a system-reset. Manually clearing memory-regions is quite risky when running software, no-init-memory-regions especially.

My question is, is there a way to trigger the full-SRAM-reset as defined in PROCOND from software? If no, do you have any recommendations how to handle uncorrectable ECC-errors after reset?

Regards
Joakim

[cwunder]

My question is, is there a way to trigger the full-SRAM-reset as defined in PROCOND from software?

There could be different ways. If you are using PMIC like the TLF35584(5) then you can cause it to issue a POR to the AURIX (could be either cold or warm).

Look into using the MTU to clear/test the SRAM memories. Please review the TC2xx Safety Manual

[joakimB · Accepted solution]

Hi, thanks for the reply.

We utilize a TLF35584, however, I cannot get it to issue a PORST since HW is set so that WAK=HIGH and MPS=HIGH, so I'm looking for alternatives.

I continued reading other forum topics and it does not seem to be any resets that activates the sram-reset unless you utilize the PORST-port.

I ended up extending the copytable and manually clearing the no-init-memory in case of detected uncorrectable ecc-error inside that memory-region.