Correct way to config hvn_tx_queue_size

[rolandash]

Just need a quick confirmation, in S140/SDK15.2, what is the correct to config hvn_tx_queue_size? 

I found in some post said it can not be set directly, instead one should only change NRF_SDH_BLE_GAP_EVENT_LENGTH.

While in other posts said it can be direct set as in here

So which one exactly should be the right way? Will change NRF_SDH_BLE_GAP_EVENT_LENGTH only work in 15.2?

thanks.

[Simonr]

Hi

You should follow Runar's advice and edit NRF_SDH_BLE_GAP_EVENT_LENGTH to change the queue size. You can set the queue size directly, but we generally don't recommend editing registers directly like that.

Best regards,

Simon

[rolandash]

thank you Simonr

So does it mean that if I set a new NRF_SDH_BLE_GAP_EVENT_LENGTH, then value of ble_gatts_conn_cfg_t::hvn_tx_queue_size will be automatically updated, and how I can read the the new hvn_tx_queue_size value out ?

 

[Simonr]

Depending on how much you want to change the queue size, you might have to increase NRF_SDH_BLE_GATT_MAX_MTU_SIZE as well to increase the static MTU size and NRF_SDH_BLE_GAP_DATA_LENGTH to increase the data length to be negotiated. So yes, hvn_tx_queue_size will be indirectly configured by the SoftDevice, based on what the EVENT_LENGTH and DATA_LENGTH is set to.

Best regards,

Simon

[rolandash]

Simonr

Do you know any place to read the exact value.of hvn_tx_queue_size out that can be used in other place in program? there seems no api function to read it.

[Simonr]

Correct, there is no API function for this.

Best regards,

Simon