nRF51 transfer speed from android

[fabian]

Hi,

i am not able to send (write characteristic) from android at a higher transfer-rate than 2.3 kbit/second. With another Bluetooth LE peripheral i get more than 100kbit, so it can't be a limitation of Bluetooth LE I tried playing with intervals which brought me from less than 0.5 kbit/sec to where i am. Not any further.....

The mentioned BLE_OPT_CONN_BW_SET did not work yet, still trying to find more spec here. [edit] i figured how to configure the bandwidth-RTFM helps. Still dog slow when "sending", "receiving" via notifications is "fast" with approx. 30kbit/second with HIGH bandwidth and 4 kbit/second with low bandwidth [/edit]

Any idea what i am doing wrong or where my setup does not work?

[update] I finally figured, if i change the android app to write without response it gets fast as hell (~100kbit/second). Why is it so dog slow when using write with response? [/update]

cheers

Fabian

[Petter Myhre]

With write command/write without response you can send multiple packets in a connection interval. With write request/write with response you can only send one packet in a connection interval. It will have to wait for the response before it can send a new packet.

[fabian]

Thank you Petter,

i did not expect is was 25 times slower when waiting for acknowledgement.....

Anyhow, this is fine for me now.

Thank you

Fabian