how many packets per connection interval 52832

RE: how many packets per connection interval 52832

bluebeam — Mon, 26 Mar 2018 23:15:57 GMT

I didn't handle the TX_COMPLETE message since it's just testing code. Basically I was calling the function in a while loop until I get the error BLE_ERROR_NO_TX_PACKETS:

do{

... ...

err_code = sd_ble_gatts_hvx(m_conn_state.conn_handle, &hvx_params);

}while(err_code == NRF_SUCCESS);

I just wan to understand how the TX buffering works in soft device.

RE: how many packets per connection interval 52832

Turbo J — Fri, 23 Mar 2018 15:18:54 GMT

You also have to handle the TX messages, unless your BLE stuff runs in an interrupt context. The internal buffers are IMHO only free'd when the corresponding TX message was processed.

RE: how many packets per connection interval 52832

bluebeam — Fri, 23 Mar 2018 06:40:01 GMT

That's just my test code. So I did it in a while loop. That's as fast as application code can run to feed the buffer. I didn't use any data buffer of my own.

RE: how many packets per connection interval 52832

Turbo J — Thu, 22 Mar 2018 10:08:43 GMT

Looking at my own performance numbers, the NRF52832 seems to be fast enough that you can queue new TX packets during a connection event. But that depends a lot on how fast your feeding code is - I used a rather large (KB sized) FIFO.

Note that the central may also limit the amount of data transferred in one interval. Note that Apple says the connection interval should be 30ms.