Change Connection Parameters on the Fly

RE: Change Connection Parameters on the Fly

run_ar — Mon, 23 Nov 2015 06:48:15 GMT

Sorry, I tested from the nRF51 side, but looking at the Android API I guess you could do this with request connection priority.

RE: Change Connection Parameters on the Fly

danbujak — Fri, 20 Nov 2015 15:01:57 GMT

What mechanism did you use to send the connection parameter update request? You're able to make this request from the android side?

RE: Change Connection Parameters on the Fly

run_ar — Fri, 20 Nov 2015 08:36:00 GMT

Just did a test where I send aconnection parameter update request every 30th second. As far as I can see this works just fine. The test was done on:
1.Nexus 6 running Android 6.0
2.Samsung galaxy S4 with Android 5.0.1.

RE: Change Connection Parameters on the Fly

awneil — Wed, 11 Nov 2015 10:27:54 GMT

Jut found this - might be worthy of note:

devzone.nordicsemi.com/.../

RE: Change Connection Parameters on the Fly

danbujak — Mon, 09 Nov 2015 19:22:08 GMT

Thanks for the suggestion run_ar but the problem is we need to send very small amounts of data and quite infrequently but the response time needs to be fairly quick for the user experience. Ideally this would really need to be an android solution, so if what you're saying is true then that would be great. However, I also fear it may be wishful thinking :P

RE: Change Connection Parameters on the Fly

run_ar — Mon, 09 Nov 2015 19:19:24 GMT

awneil: Yes, change timing is similar for the nRF8001, in ble-sdk-arduino the command is lib_aci_change_timing or lib_aci_change_timing_GAP_PPCP (to use the preprogrammed connection parameters).

danbujak: One possibility could be to still use slave latency and have a characteristic that tells the slave that you want to transfer data. Then the slave can stay awake (by sending dummy data or something) to receive the data you want to send it. Not sure for how long periods you need to send data. But it is a possible workaround if the restriction is there in Android. However I will check with our Android expert if it is possible to change the connection interval more often (I think it is in the newer versions, but it could be just wishful thinking...)

RE: Change Connection Parameters on the Fly

danbujak — Mon, 09 Nov 2015 15:19:41 GMT

The problem is that we need low latency from the master to the slave, and low power consumption on the slave.

RE: Change Connection Parameters on the Fly

run_ar — Mon, 09 Nov 2015 06:35:26 GMT

One option could be to use slave latency, this way you can have low latency from the slave to the master when needed, but you can have low power consumption on the slave when you don't need the fast connection interval. The master will still have to send a packet every connection event.

RE: Change Connection Parameters on the Fly

Dave_couling — Fri, 06 Nov 2015 19:33:44 GMT

Be careful, I believe on Android, you are only allowed one Connection Parameter update per connection (Not sure if this has changed with the new OS). All subsequent Connection Parameter Update requests from the peripheral will be ignored by the phone.

-DC

RE: Change Connection Parameters on the Fly

awneil — Fri, 06 Nov 2015 16:50:29 GMT

Same question for nRF8001!

Is it similarly just a case of issuing a ChangeTimingRequest ?

RE: Change Connection Parameters on the Fly

danbujak — Fri, 06 Nov 2015 16:18:40 GMT

Thanks, I just amended the question to include use case 2 where the central is an android device.

RE: Change Connection Parameters on the Fly

Wojtek — Fri, 06 Nov 2015 16:15:02 GMT

Sure it is. Just sd_ble_gap_conn_param_update.