Added a short delay to ensure timely PDOs #111
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src/jsd.c
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| ecx_writestate(&self->ecx_context, 0); | ||
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| int attempt = 0; | ||
| while (true) { | ||
| struct timespec current_time; | ||
| clock_gettime(CLOCK_REALTIME, ¤t_time); | ||
| if ((start_processdata_time.tv_nsec - current_time.tv_nsec)/1e3 > timeout_us) { |
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In start_processdata_time.tv_nsec - current_time.tv_nsec)/1e3, doesn't this always evaluate to a negative number since you are updating current_time so it's increasing, but start_processdata_time is stale from when it was first measured in L168?
Is that your intent here to always go into the else clause and then do a nanosleep(&diff)?
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Oof I actually fixed this locally for Ernest's fork but never changed it here. I'll fix this now XD
Hey @dwai-wai, |
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I just have one documentation nit left, but I think the code changes achieves what is recommended OpenEtherCATsociety/SOEM#224
| MSG_DEBUG("Went over the loop period!"); | ||
| } | ||
| else { | ||
| struct timespec diff; |
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Nit: To help a future maintainer, I think it would be nice to add
"Do a nanosleep until the next tick as defined by timeout_us before attempting to do a receive_processdata so that we can send LRW packets at a constant interval to encourage a successful transition to OP state"
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Thanks all LGTM, just need a codeowner's approval before merging (I am not a codeowner D: )
It was found that some devices, specifically Platinum drives, would not transition into operational state. From debugging, research, and headaches, it was found that the issue was due to non-timely sending of PDOs. When PDOs are not sent at a timely rate, the slave will not transition to Operational mode.
This information is presented here:
OpenEtherCATsociety/SOEM#224
"Mostly a 1ms cycle time will work. When the slave sees enough LRW packets at a constant interval it will lock to that and release to Operational."