Scan in a Single Channel

[FA]

Hi,

As mentioned in this post: devzone.nordicsemi.com/.../

the struct ble_gap_adv_params_t --> ble_gap_adv_ch_mask_t give the option to turn any advertising channel OFF. I tested this approach and could advertise on only one channel.

The problem that I found was in scanning for this packet. When I'm using 3 channels for advertising, the scanning program is ALWAYS able to pick the advertising packet. But when I'm using 1 channel for advertising it misses some. Is there any way to program the scanning so that it only looks on a single channel? Can this problem be due to values of scan interval and scan window (I'm setting them equal to continuously scan)?

In the description of ble_gap_adv_ch_mask_t (infocenter.nordicsemi.com/index.jsp it says "Channel mask for RF channels used in advertising and scanning". But I could only found a place in the ble_gap_adv_params_t to pass it, and ble_gap_scan_params_t doesn't have this field.

So how can we set this feature for scan mode?

[Hung Bui]

Hi FA,

Scanning with selective channel(s) is not supported yet. I will report internally to fix it in the documentation.

Thanks for reporting.

If you want to do scanning on single channel, you may want to have a look at this observer example. We do scanning manually on S110 softdevice using timeslot feature.

ble_app_proximity - Observer.zip

[Hung Bui]

1. No there should be no difference. But you would need to use the correct API headers matching with your Softdevice (S110 or S130). You mentioned it didn't work, could you be more specific ?

2. Yes, the example on github created for S110.

When you remove softdevice_handler.c, please make sure you have in your SWI2_IRQHandler that you fetch all the system event out, and handle them correctly. Including the pstorage event handle. My suggestion for you is to port the example on Github to SDK 9. After that you add your own application code in.