Sending critical data in advertisement from ble app uart peripheral device to central device

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

David Edwin — Wed, 19 Aug 2015 09:19:15 GMT

Scan window of 30ms and interval of 60ms can be a start point (this gives a duty cycle of 50%).

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Brajesh — Wed, 19 Aug 2015 09:03:49 GMT

One more point Edwin, since Adv interval is 20ms, having scan window larger than that would help, right ?

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Brajesh — Wed, 19 Aug 2015 08:37:16 GMT

Thanks Edwin, I'll try that surely & will let you know.

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

David Edwin — Wed, 19 Aug 2015 07:36:29 GMT

Duty cycle is the scan interval and the scan window, so set it to a value that uses the radio as a scanner 50% of the time. Check if your adv report frequency is getting better or worse.

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Brajesh — Tue, 18 Aug 2015 18:04:42 GMT

That's a very valid and helpful point. I'll be checking the duplicate filtering and if it is the what adv data shall I change to come out of filter ... anyway I'm changing one byte for every notification from peripheral side.

Also what do you mean by reducing the duty cycle? Does it have to do with scan window and interval? ?

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

David Edwin — Tue, 18 Aug 2015 11:03:31 GMT

The only comment that I have on centrals is that you may want to check the options that drop duplicate advertsisements , you may also want to change the data that you are sending periodically so that if there is duplicate filtering on the central side this does not become an issue. I would also suggest that you reduce the scan duty cycle to about 50% duty cycle and see what you observe.

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Petter Myhre — Tue, 18 Aug 2015 10:58:15 GMT

It is. I don't think there is anything more you can do one the peripheral side. I don't know how to help you with the TI central device, sorry.

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Brajesh — Tue, 18 Aug 2015 10:00:12 GMT

Petter, adv interval is 20ms which is i think is fastest adv interval.

Central device is TI's WL1837, and scanning is also continuous , & Peripheral is nRF51822.

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

David Edwin — Tue, 18 Aug 2015 09:27:39 GMT

Please provide more details on the central device and your peripheral device. Names of those devices ? Hardware versions , firmware versions etc .

RE: Sending critical data in advertisement from ble app uart peripheral device to central device

Petter Myhre — Tue, 18 Aug 2015 09:09:59 GMT

What is your advertising interval?