How UNreliable is notification? Or is this notification's fault?

[Mitch996]

I'm trying to send a string of bytes from nrf51822 to an android device.

I'm using notification.

There will be potentially thousands of data to be sent from nrf51822 to android.

For some reason, I can only send a limited number, 6 so far, it's way less than I had hoped for.

My android device is kind of obsolete, it was bought in 2013.

I understand the whole thing - using notificaction to send a large amount of data- may not be a great idea, but for now, I'm working on a prototype product, therefore 50 times per session will be fine. But so far, as I mentioned above, I got only 6. Beyond that my android program stops being responsive.

It could be the fault of the android device, but I want some expert idea on how bad an idea this is, you know, to send data using notification from nrf51822 to android? I mean, it could be quite reliable actually, if that is the case, I'll shift my debugging focus from nrf51822 to android.

Also, should I use notification?

[RK]

It isn't unreliable at all. Notifications/indications and every other communication at the link level are 100% reliable. If a packet is accepted by the softdevice it's sent, if it's sent it's received, in order, totally guaranteed unless the link actually times out (at which point you get a link timeout). Although the spec allows notifications to be dropped at the receiving end I have yet to come across an implementation which does that as it would be stupid, you've received the packet, even a brain-dead android device from 2013 has enough buffer space to deliver it to your application.

Instead of shifting your debugging focus, how about writing a better question about what you mean by 'wanting to send 50' but 'only being able to send 6'. And what is a 'session'? For all I can tell you're pumping out notifications, ignoring the reply which says you don't have a buffer left to send them and are wondering why most of them don't get through.

People send absolute *** tons of data absolutely reliably using notifications, at great speed, it's actually pretty much THE best way to send a lot of data over BLE as fast as possible. So you're just doing something wrong.

[Mitch996]

It's all successful. Nothing wrong with the nrf51822 I figure. I'm still working on the android code. Must be that. Will get back later if that is the case.