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Thanks, please see below.
thank you very much for your shared issue related PD.
The state NOPOWER keep in account the exit way of a PD to reach turn off and the idea is limit the PD power up to 44mA during VPD<Voff_PD.
Yair: I understand that this was one of the objectives however right now what we add creates the two problems that I show, cause violating of the spec of compliant PDs.
Please note that compliant PDs will not need to use the exits to NOPOWER due to the fact that PD voltage is not allowed to consume more than Pclass_PD so there is no reason that VPD will go below VOFF_PD and PSE is not allowed to reduce its output voltage below operating voltage during normal operation except transient overload or short circuit conditions which in this case we mat shut off the port or in case of transients which PD is required to work. The addition of NOPOWER was added to handle PDs that from some reason their input voltage fall below Voff and then raised above Von which in the real world may happen and during the transition from Voff to Von the PD counts additional class event continue to count (which compliant PDs doesn’t allowed to do, since the class event counter should be locked after the first time going to INRUSH) and people thought that we have aslo to handle this case.
So please consider how we address the issues of violating the 80msec timer and causing overload condition after entering the NOPOWER state. We have to fix this.
The introduction of a further variable that regulate a possible (or not) use of that way is not my preferred approach.
Yair: Please explain why if this is optional and compliant PDs doesn’t have the problems that cause PD to go to NOPWER.
Maybe is possible to evaluate to remove the exit from POWER_DELAY to NOPOWER.
Yair: We thought about this solution and it will fix part of the problem (the first issue). The issue with this solution is: If you believe that we should address the case when VPD<VOFF, you should address this in all the states that the PD is powered including POWER_DELAY. Otherwise how you explain that your are doing in in POWERED and not in POWER_DELAY?
The proposed solution fix this problem by either you address is with the risk of having the two issues but then we don’t care since any way it was non-compliant behavior. Or chose not to use this option and then there is no issues.
While the point related to the pse_power_level <==8 I think that your proposal is a right suggestion but it should be implemented in the definition of pse_power_level variable.
Yair: It is OK by me to address the pse_power_level <==8 in the definition of pse_power_level variable.
2017-10-20 1:12 GMT+02:00 Yair Darshan <YDarshan@xxxxxxxxxxxxx>: