How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

rav4 — Fri, 01 Mar 2019 10:04:04 GMT

Got it. Thanks.

RE: How to obtained BLE frequency hopping table from SoftDevice

haakonsh — Fri, 01 Mar 2019 10:02:14 GMT

Typedefs
typedef uint8_t	ble_gap_ch_mask_t [5]
	Channel mask (40 bits). Every channel is represented with a bit positioned as per channel index defined in Bluetooth Core Specification v5.0, Vol 6, Part B, Section 1.4.1. The LSB contained in array element 0 represents channel index 0, and bit 39 represents channel index 39. If a bit is set to 1, the channel is not used.

RE: How to obtained BLE frequency hopping table from SoftDevice

haakonsh — Fri, 01 Mar 2019 10:01:41 GMT

That is true, I've been schooled! :3

RE: How to obtained BLE frequency hopping table from SoftDevice

rav4 — Fri, 01 Mar 2019 02:00:57 GMT

Hi Håkon,

thanks. I managed to read back the channel map. May I know how to decode the value? All the channels are marked with '0'? Does it mean all channels are used? Or the value is invalid. The channel map was read at 1 second interval for testing purposes.

thanks.

RE: How to obtained BLE frequency hopping table from SoftDevice

Dmitry — Thu, 28 Feb 2019 10:32:47 GMT

In fact, host sometimes updates channel map. You can try to use sd_ble_opt_get() with BLE_GAP_OPT_CH_MAP to read channel map.

RE: How to obtained BLE frequency hopping table from SoftDevice

haakonsh — Thu, 28 Feb 2019 09:50:27 GMT

BT/BLE does not yet use adaptive frequency hopping, you have to manually disable channels with a call to sd_ble_opt_set where you pass a ble_gap_opt_t of ble_gap_opt_ch_map_t.

See also ble_gap_ch_mask_t.

RE: How to obtained BLE frequency hopping table from SoftDevice

rav4 — Thu, 28 Feb 2019 09:11:31 GMT

Håkon,

I understand that BT/BLE uses adaptive frequency hopping mechanism where central/device will mask out the channels used by Wifi. Is this applicable in my use case?

By the way, how to disable data channel? Which API to use?

thanks.

rav4

RE: How to obtained BLE frequency hopping table from SoftDevice

haakonsh — Thu, 28 Feb 2019 08:44:28 GMT

Hey rav4,

There's no API to fetch the current channel map, but as long as you've not disabled a data channel then all data channels are used. If you have disabled one or more data channels then you already know the channel map.

Cheers,

Håkon.

How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

Typedefs

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice

RE: How to obtained BLE frequency hopping table from SoftDevice