Hello Richard, > > Do I need any further permissions for my sourceforge account to view the > > archives? > > I just fiddled with the SF settings for the lists. Can you see it now? > > (I have been recommending gmane instead, but that site went down.)
I still get the same error (Error 403, Read access required). > > LinuxPTP 802.1AS issues: > > > > 1) phc2sys does not work if transportSpecific is set to 1 > > > > When I set transportSpecific to 1 (as required by 802.1AS) in my config > > file, the phc2sys tool does not work. > > My test config file looks as follows: > > > > $ cat TestConfig.cfg > > > > [global] > > transportSpecific 1 > > > > When I call ptp4l with "sudo ptp4l -f TestConfig.cfg -i enp2s0 -p > > /dev/ptp0 -m" (without that config file) and phc2sys with "sudo > > phc2sys -a -r -r -m -S 0.2 -F 0.2" it only prints > > "phc2sys[5236.261]: Waiting for ptp4l..." every second. If I start > > ptp4l without that config file or comment out that one line, phc2sys > > works as expected. > > Can you try this instead? > > [global] > [enp2s0] > # > # Not in the global section! > # > transportSpecific 1 > > This is bug where the gloabl transportSpecific setting is being > applied to the UDS interface. I'll fix this soon. Thanks for the hint, with this configuration it works as expected. > > 2) Differences in the BMC algorithm > > > > Is it possible to specify a different best master clock algorithm than that > > of the default PTP profile? > > No, not yet. I have some patches in the works for allowing different > BMC variants, because some profiles will require it. > > However, the AS mode should work fine with the default BMC... > Ok, thanks for the clarification. > > The BMCA of the default PTP profile and 802.1AS are similar, but not the > > same. > > Noticable differences are: > > > > *) There is no pre-master state in 802.1AS > > This only causes a master to wait an additional announce period before > sending the first announce and sync messages. It doesn't affect how > we inter-operate in a gPTP network. > > > *) There is no foreign master qualification in 802.1AS > > Again, this doesn't affect correctness WRT how we inter-operate. This > only affects the slave, causing a short delay before starting > (internal) synchronization. > > > *) If a master stops sending sync messages but still sends announce > > messages, this should trigger a state change in the slave according to > > 802.1AS (configured via syncReceiptTimeoutTime), while it is fine in > > default PTP. > > This is implemented. Did you test this? Sorry, this is my fault. I just checked my config and syncReceiptTimeout is set to 0. I thought I had already changed it on my test device. > > 3) PDelay uses wrong clock > > > > 802.1AS specifies in 11.1.2 the following: > > > > "In practice, t1 and t4 are measured relative to the LocalClock entity of > > the initiator time-aware system, and t2 and t3 are measured relative to the > > LocalClock entity of the responder time-aware system." > > > > The LocalClock in 802.1AS is a local free running oscillator, in contrast > > to the recovered clock that is created via PTP. > > However, I see in the t2 and t3 timestamps of my LinuxPTP instances times > > refering to the time that is transfered via PTP. > > No, the interval T3-T2 is converted into the local time base. > See get_raw_delay(). I will have a lock at it. > > 4) Path Trace TLV > > > > Announce messages without a Path Trace TLV are ignored by my device if I > > set path_trace_enabled to 1. > > I think in 802.1AS a Path Trace TLV should be attached to announce > > messages, but announce messages should not be dropped if a received message > > does not have one. > > First you complain that we don't follow AS exactly, and then you > complain that we *do* follow it exactly! Please don't get me wrong, I'm not complaining :) I just want to discuss what seemed non-compliant. > Path Trace is specified in 10.5.3, and there is no hint of it being > optional. In fact, this is required in the PICS. Any master who > sends an Announce must conform. Look at page 240. > > MIMSTR-8 Does the Announce message body comply > with the requirements in 10.5.3.1 and > Table 10-7? > > @Delio, I see you allow announce without the TLV: > > > https://github.com/audioscience/linuxptp/commit/0b6d8ca73332391af9bddc25177df254b066d669 > > Can you tell us why? > > > 5) The PPS signal produced by the i210 seems to be unreliable > > > > I know that the right place to discuss i210 problems would be LMKL, I just > > mention this here as I assume several of you might have experience with > > this chip. > > I observe that if I enable the PPS signal on the software definable pins of > > the i210 it initially works fine. > > But if there are state changes in the PTP stack because I unplug/replug > > other devices to the network, the PPS signal of the i210 can disappear. > > Calling the corresponding ioctls again (and thus setting the register of > > the i210 again) restores the signal. > > Does this match your experience? > > Yes. You must stop and restart again whenever the time jumps. You > should write a script to monitor ptp4l and restart when needed. Ok, thanks for the information! This leads to another point that I have not figured out yet. If I would like to get notified in another program about PTP state changes, what is the preferred interface? regards, Wolfgang PS: I forgot to set the mail subject in my initial mailing list post in the morning. Should we change the subject to something meaningful like "802.1AS discussion" now or would that cause trouble with the e.g. the thread view in mailing list archives? ------------------------------------------------------------------------------ The Command Line: Reinvented for Modern Developers Did the resurgence of CLI tooling catch you by surprise? Reconnect with the command line and become more productive. Learn the new .NET and ASP.NET CLI. 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