does nrf51 softdevice can connect with specific channel?

[Daniel T. Lee]

As I know, BLE Advertising on 37, 38 ,39 channel and I can select which channel to advertise by masking them.

But, Is it possible to make an data connection to a channel as I want (from 1~38)?

Easily, can I choose which channel to communicate with Peripheral or Central?

I really tried to search for it, but I can't found such thing like that.

I think which channel to connected is all softdevice's desire.

Can I manage or choose which channel to data connection?

If I can, then How can I achive it?

[RK]

You could try sd_ble_opt_set with the option ble_gap_opt_ch_map_t and set a one-channel channel map. I really don't know why you'd want to do that however as any interference will probably result in loss of connection. There's a reason bluetooth uses 37 channels.

[Daniel T. Lee]

thanks! actually, I'm trying to use lot's of BLE Connections, maybe more than 37 Channels + and also, It could be interrupted with other 2.4Ghz Channel such as Wireless Keyboard, Wi-Fi or Etc.

In this situation, I'm really worried that my BLE Packet would drop. So I was trying to find out that I can manually scan how many other device use specific channel, and trying to connect it dynamically.

does nrf sd_ble_gap_connect automatically scan all 37 channel and it select's the most smooth channel? or it just use any channel that nrf just wants to (or random channel)? (I call this dynamic scan and connect to most appropriate channel as an active scanning. does this have official terms for this?)