[Petra-Kathi]

Hello @all,

I use two old Samsung (SM P-900, SM P-905) tablets in book mode with a bluetooth connection between them, and another BT connection from the master to a foot pedal. (BT is fine in changing environments as it creates a "network" of its own, and you don't have to rely on availabilities of wifi connectability.)

Somehow I managed to make the connection between the tablets work for the score display and the foot pedal paging, but I don't seem to get the incremental score library updating (synchronization between master and servant) up and running. So far I managed that with uploading/integrating new scores on the master, then creating/exporting a complete backup on the master / on the desktop system, and then uploading and  restoring this backup on the servent tablet. But with a growing library I'd expect a differential update of the servant to become more and more effective.

As the tablets cooperate already w/r/to song selection and paging in normal operation mode I'd expect to invoke lib synchronization to work without any further connectivity setups (apart from defining the transmission contents, control parameter settings, and which device acts as what). But the connection seems to not get started and going. And I don't understand the error messages telling me that the connection cannot be established?!?

Any help greatly appreciated!

Petra

[Zubersoft]

Each feature uses its own connection (otherwise you could get cross talk that could cause problems if they all shared a single connection). Your device probably has a limit on the number of simultaneous bluetooth connections (some devices have a limit as low as 3) which is why you encounter an error when trying to establish another one. That's just my guess based on your description. Synchronizing a library over bluetooth is generally a bad idea compared to WiFi, as the bluetooth protocol is abysmal for handling transfers of large amounts of data. I would recommend using WiFi for that. I have been considering just removing bluetooth as an option for library synchronization as it's quite problematic (and not entirely reliable).

Mike

[Petra-Kathi]

Hi Mike,

thanks a lot for the fast response and clarifications about the potential connection limits. I don't think that they are hit in my case, though. And I definitely contemplate your warnings about the unsafe BT connections for large data amounts. I'd just like to use the BT connection for the library synchronization after uploading, say, one or two pieces to the master tablet. (So far I managed this by creating a complete backup of the master, transferred that to the desktop comp, reconnected that wifi-wise to the servant tablet, and restored the complete library there. What deems me like an overkill for the small amount of data that really *needs* to be transferred.)

Nevertheless I'd like to lighten up my understanding of the processes involved. I don't want to die dumb. 

My BT setup: Master tablet named PNT-01, servant tablet named PNT-02 (additionally a Donner BT foot switch, let's call it BMP.)

Opening the BT settings on both tablets it says on the Master: BMP and PNT-02 coupled. On the servant: PNT-01 coupled. So far, so good, I'd say.

Additionally there is an "available" device named "TG" which I do not remember to have set up or any pointer as to what that may be. I don't expect any further BT device in the nearer vicinity. This device is not shown at later  times.


My usual procedure using MSP:

# open MSP on master, and as soon as fingers allow, open MSP on servant.

# master asks me to show connection for 120 s -> confirmed -> tablets connect to each other, confirmed by the fact that the book mode works when selecting any multipage piece. Foot switch operative.


Now to the malfunctioning library synchronization (I translate the German dialogs to their presumable English pendants; sorry if this is not correct to the last letter ;-))

# Choosing "synchronize library" on both tablets, choosing a syc type: "Sync to a device"

# On master: "connect as server", on servant: "connect as client"  (I only want the one-way sync!)

# On master: Choosing "create server" -> busy sign begins to rotate. (In some trials the question to publish the BT connection for 120 s shows up. If so, I agree to that.)

# on servant: Choosing "connect", with searching switched to on -> PNT-01 appears in connected devices list with green colour. Additionally there is sometimes another device called TG I still cannot interpret. Going into the device's BT setup screen this is not shown. Only the connection to the PNT-01 is given there.

# activating "connect" -> "connection to PNT-01 cannot be established"

There are no other connections (apart from wifi connections of each tablet to the house network) I am aware of.

I am quite convinced that the error lies between my headphones , but I'd love to get a pointer to where to search for it!

Kind regards,
Petra

[Geoff Bacon]

You could try wifi using a mobile phone as a hot spot for the duration of the sync.
Don't forget to turn the hotspot off after the transfer!

Geoff

[Petra-Kathi]

You could try wifi using a mobile phone as a hot spot for the duration of the sync.
Don't forget to turn the hotspot off after the transfer!

Hmm, AFAIK devices connected via a phone hot spot (to the internet) cannot see each other in the local network? If so, the sync between them would need additional information to be passed for any occasional setup - which is rather impractical.

But thanks for the basic idea!

Petra

[Geoff Bacon]

Confusing - googling for "wireless hotspot local devices seeing each other" produces AI output that says
"Yes, when devices are connected to the same wireless hotspot, they can typically see each other and communicate on the local network. This is because the hotspot acts as a router, allowing devices on its network to access each other's resources, like file sharing or accessing a web server running on another device. However, some routers offer guest networks that isolate devices, preventing them from seeing each other."

As I read this, your two devices should be able to talk to each other (assuming they are both connected to the hot spot)

Geoff

[Zubersoft]

It's also possible that the Android framework either doesn't allow or has problems with having multiple simultaneous bluetooth connections with the same device (as that isn't normally possible). If that's the case, then I would have no choice but to share the same bluetooth connection between multiple features, but they weren't designed with this in mind so it would cause all sorts of havoc at the moment. So I think if you want to use bluetooth for both, you may have to disconnect the "Connect Tablets" feature, then sync the library, then reconnect the "Connect Tablets" feature.

Mike

[Petra-Kathi]

Hi Geoff,

...
As I read this, your two devices should be able to talk to each other (assuming they are both connected to the hot spot)
...

I have to beg your pardon!  

You are right: After initializing the tethering and connecting both tabs to this network they do see each other. I tested it only once several years ago (being quite a long-term user of MSP) with a negative result then. And I noticed now that after setting up the server side the servant side sees/finds its master automagically.  

Thanks a lot for the nudge!

Petra