how to enable 2mbps

[cann0021]

Hello everybody.

I have two boards. I have been trying to build a communication between my boards for a time. I could not manage to have 2mbps data transfer rate. 

Boards                    : nRF52832 DK(PCA10040) and nRF52840 Dongle(PCA10059)
SDK version           : 15.3.0
SoftDevice Version : 6.1.1
SoftDevices            : s132 for PCA10040 and s140 for PCA10059
Examples               : ble_app_uart and ble_app_uart_c

1-) How can I enable 2mbps data transfer rate ? I have tried various methods like sending PHY updating requests etc. But I guess I am doing something wrong. What is the correct way to do it?
2-) Let's say I managed to have 2mbps data transfer rate. How can I test it ? How to verify that I am having 2mbps data transfer rate ?

Sincerely.

[Simonr]

Hello

To ensure 2Mbps, please make sure that the PHY you're using is BLE_GAP_PHY_2MBPS in both central and peripheral. In order to maximize the throughput, you should also sett the ATT MTU to 247 bytes, enable Data Length Extension (DLE), and increase your connection interval. You can check out this blog post, where the maximum throughout in BLE 5.0 has been tested using two nRF52840 chips.

Best regards,

Simon

[cann0021]

Hello Mr. Simonr.

Thank you for the answer. How can I set BLE_GAP_PHY_2MBPS ? Where to set ? How can I enable Data Length Extension? By the way, I have already read that blog post. But how can I implement those things with nRF ?

[Simonr]

On the peripheral side, you can add adv_params.primary_phy = BLE_GAP_PHY_2MBPS; to the advertising_init() function. On the central side, you can add  .scan_phys     = BLE_GAP_PHY_2MBPS to the ble_gap_scan_params_t function. You should also add 

                .rx_phys = BLE_GAP_PHY_2MBPS,

                .tx_phys = BLE_GAP_PHY_2MBPS,

to the BLE_GAP_EVT_PHY_UPDATE_REQUEST.

Please check out this case for how to enable and check for Data Length Extension and MTU.

Best regards,

Simon

[cann0021]

For the peripheral, there is nothing like adv_params. Instead of it, I added init.config.ble_adv_primary_phy = BLE_GAP_PHY_2MBPS;

But now, it causes FATAL_ERROR.

[Simonr]

Hi

Try adding the following to your advertising_init() function:

    init.config.ble_adv_primary_phy      = BLE_GAP_PHY_2MBPS;
    init.config.ble_adv_secondary_phy    = BLE_GAP_PHY_2MBPS;
    init.config.ble_adv_extended_enabled = true;

Best regards,

Simon