Activity for drkfrxâ
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #293118 |
Post edited: Added missing link to memfault article |
— | 2 days ago |
| Comment | Post #293118 |
I really appreciate it, but I can hardly disclose the specifics :(
I was told we're aiming for Class B certification, which says system reset are acceptable. Hardware mods would be more costly than patching it with a system watchdog so I guess that only leaves 1 solution. (more) |
— | 5 days ago |
| Comment | Post #293120 |
I admit I didn't think about memory corruption. So there could be an edge case where memory gets corrupted but all parts of the firmware still run, albeit in an incorrect manner. The watchdog could still be fed nonetheless and have the system sustain in this faulty state.
This feels quite improbab... (more) |
— | 5 days ago |
| Comment | Post #293118 |
You raise valid points. We'll conduct further investigation, though as of now, we suspect failure of an external IC due to ESD on the SPI line. (more) |
— | 5 days ago |
| Comment | Post #293120 |
Thanks for that, I was looking for a more nuanced answer like this. My system is bare metal and part of the firmware is interrupt driven by an external IC. The watchdog needs to trigger if said external IC fails to raise its IRQ line. I had implemented the conditional feeding with the "event flags" a... (more) |
— | 5 days ago |
| Comment | Post #293119 |
I understand what you are saying, so that would be the typical approach. However, in my case, I have a few critical routines that are executed inside high priority ISR; the main loop isn't aware of those. This forces me to implement a conditional watchdog feeding process because if 1 of the critical ... (more) |
— | 5 days ago |
| Edit | Post #293118 |
Post edited: Added more information regarding the ESD tests |
— | 5 days ago |
| Edit | Post #293118 | Initial revision | — | 5 days ago |
| Question | — |
Is Feeding a Watchdog Timer from an ISR a Bad Practice? In an embedded system, I require a watchdog to be able to pass ESD qualifications (the main reason for the watchdog requirement is that the device wasn't able to pass the harshest tests of the IEC 61000-4-2 standard). Having no experience with watchdogs, I went through this Memfault article. I liked ... (more) |
— | 5 days ago |