How to increase Data Rate

[Ferhat B]

Hi

We use ble_app_uart_pca10040 app. We have our own board has microcontroller and send data over uart to ble module (bmd350) There is Nrf52832. I want to send 32byte pack and 500pack in sec. Im very far to achive that.

Ferhat

[Sigurd]

Hi,

Is it the BLE data rate you want to increase? What are you connecting against? A smartphone?

You can lower the connection interval by changing the MIN_CONN_INTERVAL and MAX_CONN_INTERVAL values. Try setting it to e.g :

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(7.5, UNIT_1_25_MS) 
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(20, UNIT_1_25_MS) 

There are also several other things you can do to increase the data rate. Such as increasing the ATT MTU size, enable Data length extension (DLE) and enable Connection event length extension.

[Sigurd]

Yes, smartphones/tablet typically supports between 4-6 packets per connection interval. If the smartphone/tablet supports ATT MTU 158 bytes, then you can set m_ble_nus_max_data_len to 158. This is done automatically for you in the function gatt_evt_handler().

“In soft device document is see for client Att MTU 23 and 7.5ms”. It can be set to up-to 247. See table 2 here.

Q: I want to transfer 120bytes one time, is it possible?

A: Yes, this is possible as long as the smartphone/tablet also support it.

Also see this answer.