RE: Send multiple notifications per connection interval

Artem Zemlyanukhin — Fri, 28 Nov 2014 16:21:03 GMT

Hi Ole,

as I can see I can't receive more than 1 packet per connection event using nRF51 dongle with Master Control Panel software. Can I receive more than 1 packet (for example 6 packets per connection event) using device with s120 software?

RE: Send multiple notifications per connection interval

Scarlet — Wed, 19 Feb 2014 05:26:25 GMT

Thanks your information!! I've tried using HTC one max to receiving data. This code can support multiple notification!!

RE: Send multiple notifications per connection interval

Ole Morten — Tue, 18 Feb 2014 15:54:50 GMT

You should note that the current master emulator dongle will support only one packet per interval, so you can't really use this for throughput testing. The trace that's available in the GitHub repository was recorded with an iPhone 4S using iOS 7.0.

However, as far as I can see, what actually happens in the trace you upload here is that the Master Emulator firmware NACKs every second packet, meaning that the peripheral retransmits it in the next interval. You can see this based on the fact that the NESN of the first packet in subsequent intervals is the same as the SN of the last packet of the previous interval, as shown in the attached screenshot.

The concept of NESN and SN is described in the Core Specification, Volume 6, Part B, section 4.5.9, which among other things state:

Upon receiving a Data Channel PDU, if the NESN bit of that Data Channel PDU is the same as transmitSeqNum, then the last sent Data Channel PDU has not been acknowledged and shall be resent.

You can add any element from the packet detail view as a column by right-clicking it and selecting "Apply as column". NESN and SN are shown in the Bluetooth Low Energy part of the detail view.