Avnu / OpenAvnu

OpenAvnu - an Avnu sponsored repository for Time Sensitive Network (TSN and AVB) technology
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How to sync two gPTP instances? #861

Open ghost opened 5 years ago

ghost commented 5 years ago

Hi!

I'm trying to get two gPTP daemon instances running in sync on two Raspberry Pi boards to check sync signal on GPIO pins. Two boards are on the same Wi-Fi network and can ping each other.

When I run one of them with -T command line switch to force it to be master and another one with -L switch to be a slave, the second one after short time interval says that after waiting for sync it becomes master too. I also add -S switch to start synchronization to both commands.

Can I achieve a master-slave connection in this case? If yes, what else am I missing? Maybe, some other command switches or something else?

Thanks.

pinealservo commented 5 years ago

This is not a configuration that will work with standard gPTP, which typically requires hardware timestamping that's not available in the RaspberryPi. There's a branch, https://github.com/AVnu/OpenAvnu/tree/feature-aptp-experimental, which adds an Apple-specific profile that is designed to work on Raspberry Pi with WiFi (and presumably interop with Apple Airplay2 devices), but I can't tell you much about how well it works or how to get it working.

ghost commented 5 years ago

This is not a configuration that will work with standard gPTP, which typically requires hardware timestamping that's not available in the RaspberryPi. There's a branch, https://github.com/AVnu/OpenAvnu/tree/feature-aptp-experimental, which adds an Apple-specific profile that is designed to work on Raspberry Pi with WiFi (and presumably interop with Apple Airplay2 devices), but I can't tell you much about how well it works or how to get it working.

Thank you for your reply!

Moreover, I have found a separate fork, https://github.com/rroussel/OpenAvnu, which have PTP daemon version with Apple profile and only with that fork I could get the build that works on RPi. Unfortunately, there is no issues section, so can't ask there.

Thanks anyway, will check.

chennakeshavaSoC commented 5 years ago

I am also trying to run the AVB on RPi and facing challenges.

@sshydlovskyi how did you managed to run on RPi? are you able to test the PTP using rroussel code? I will try the same, please let me know if any modifications to be made to work with Pi.

ghost commented 5 years ago

@chennakeshavaSoC Hi! Sorry for the delay with the answer. Yes, I think I used rrousel variant, just need to check all build options. Will write you back.