Syncing two packages on two rPis

Hi All,
Sorry to be a pest, but I’m confused and hoping someone can help me. I just got three pi Zero 2 Ms, all of which came up beautifully and are working fine. I had thought (perhaps soewhere in my fantasy world) that it would be easy to run two Scheduled Player on the same net and have them be in sync.

I have two IBs on two screens. Each setup is the same, two images that alternate every thirty seconds. The second setup is just like the first, except the order is reveresed. What I want to do is start them and keep them in sync, so that they will swap images every thirty seconds. I had ASSumed that it would be easy to schedule them that way, and it may be, but I can’t figure it out :grimacing:

Is there something simple I’m missing, or is there an example somewhere of keeping IBs in lock step? Also, when looking at times in the setup screen I’m not sure whther they are in UTC or local time. If it is in UTC is there an easy way to specify the TZ? … As I think about it, UTC makes a lot of sense for a globally distributed product.

Thanks much,

Jim Siler

The scheduled player cannot do synced playback at the moment. Only the video walls and the HD player can. What kind of content do you intend to show? Do you need the scheduling capabilities?

Thanks @infobeamer-fw Florian,
I will look at the synced playback of the HD Player. It may work for my purpose. The tight syncing isn’t critical for me, but would be nice. The scheduling is more of an issue, but as my grandfather told me, there is more than one way to skin a cat. I think that you have left enough exposed to allow me to implement and external mechanism for (hopefully) infrequent changes (e.g., Breakfast/Lunch/Dinner transitions).

Am I correct in ASSuming that the synchronization between HD players is implicit, based on starting two at the same time and relying on a high resolution synchronized clock coupled with coarsley grained fixed starting points? If so, it seems to me that startup and recovery may be tricky, whereas scheduled startup times make it borderline trivial.

I’ll play with HD Player and Scheduled Player for now, but Scheduled Player has so many things that are useful to me:

  • Scrolling ticker line
  • Tiling
  • Tilable widgets like Time
  • Plugins and the ability to create custom plugins
  • Layouts

that the lack of sync is the only thing lacking from my point of view. Syncing would be the icing on the cake, for me anyway.

Speaking of plugins, I would find a minimal sample plugin along the lines of package-food-menu (and thanks again for that one) really useful. I am going to take a stab at creating one myself, based on my modified package-food-menu, since I will need that anyway. If I’m reasonably comfortable with what I do I’ll be more than happy to make it available however you see fit.

Thanks again, and have a great weekend.

Jim Siler

Correct. It uses the wall clock time combined with the total playlist duration to derive the same starting points across any number of devices involved.

Hopefully soonish that won’t be required as a mechanism to schedule setup assignment is currently in the works. Sneak peek:

There are a few previous topics about that:

They might give you a hint on how things work. Let me know if you have any questions.

Hi Florian (@infobeamer-fw Florian),

I am a stickler (or just a crank) for correct use of language, and so I don’t use this word at all lightly, but awesome.
It seems my old grandfather was right, there is more than one way to skin a cat:

$  curl -u:$API_KEY$RIGHTPI/node/remote/trigger -d "data=SHOWSTART" \
    & curl -u:$API_KEY$LEFTPI/node/remote/trigger -d "data=SHOWSTART"

Syncs things up nicely. I have two side by side screens. The two setups display alternating 1st and 2nd pages of a menu image, each of which shows for 20 secdonds then switches to the other using a .5 second rotating transition on the y axis. Each page is based on a setup with the time in the upper right corner and a scrolling info line on the bottom. The left hand uses the first menu image as its first page and the other the second. The effect is great without being overwhelming.

I’m hoping to get comfortable with a deployment of P=rPi 4b boards so that I can do it all on one tiled virtual screen to allow the ticker line to span the monitors gracefully. Right now I can’t see any great way to do that with two pi Zero 2 Ws.

I’ve been watching the screen spin for about 1/2 hour and they still seem to be synced perfectly.

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