Timeslot extension

RE: Timeslot extension

Tong Yu — Tue, 24 Jan 2017 23:00:28 GMT

Thank you so much for the answer! Problem soloved!

RE: Timeslot extension

Ole Bauck — Tue, 24 Jan 2017 15:20:11 GMT

The NRF_RADIO_CALLBACK_SIGNAL_TYPE_EXTEND_SUCCEEDED signal or the NRF_RADIO_CALLBACK_SIGNAL_TYPE_EXTEND_FAILED signal will come right after you give the action NRF_RADIO_SIGNAL_CALLBACK_ACTION_EXTEND.

The way your code works now is that you extend the timeslot until you have successfully extended to 120 seconds. This will happen in the first milliseconds of the timeslot as you call the extend signal back to back. When you have extended the timeslot to 120 seconds you immediately ends it, long before the 120 seconds have elapsed.

What you should do is to configure the TIMER0 interrupt to fire right before the timeslot is going to expire. I have put together some code that demonstrates this, it is based on the timeslot tutorial:

timeslot.c

The timeslot will end after 120 seconds minus the margin with 600 000 successful extends.

RE: Timeslot extension

Tong Yu — Tue, 24 Jan 2017 12:28:10 GMT

fail_count was declared as static, I changed to volatile, the result was the same. I am not familiar with debug, but I set a break point at "case NRF_RADIO_CALLBACK_SIGNAL_TYPE_EXTEND_FAILED", the application did not run to that point. You mean the reason why the real extension time is short should be extension failure? So if assume nothing goes wrong, the real extend time should be 120s? I did only initialized the SoftDevice(no connection and advertising) all the time.

RE: Timeslot extension

Ole Bauck — Tue, 24 Jan 2017 11:37:48 GMT

And fail_count is declared as volatile? You should put a breakpoint in the case and go into debug mode to check if you get the extend failed signal.

How many extends do you get?

Do you get the problem if you are not in a connection and not advertising or scanning (only initialized the SoftDevice)?

RE: Timeslot extension

Tong Yu — Tue, 24 Jan 2017 11:29:45 GMT

Thanks, but I don't think I got any extension failed signal, because I kept counting all the time, if there is any failure, the "fail_count" shouldn't be 0.

RE: Timeslot extension

Ole Bauck — Tue, 24 Jan 2017 10:23:16 GMT

You check if you get the callback signal NRF_RADIO_CALLBACK_SIGNAL_TYPE_EXTEND_FAILED or NRF_RADIO_CALLBACK_SIGNAL_TYPE_EXTEND_SUCCEEDED? See the radio timeslot extension example in the SoftDevice specification.

If you try to extend the the timeslot and this will conflict with already scheduled SoftDevice activities of equal or higher priority you will get the extend failed signal. See here and here for more info on the scheduler and the SoftDevice priorities.