Change Connection Parameters on the Fly

[danbujak]

I'd like to be able to change the connection interval from my central device on the fly after a BLE connection has been established between it and the peripheral. What's the proper way to go about doing this? Is it possible without dropping the connection?

In one use case both devices are nRF51822, and in the other the peripheral is an nRF51822 while the central is an android device.

[Wojtek]

Sure it is. Just sd_ble_gap_conn_param_update.

[run_ar]

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...)