RE: BLE UART Slow Transfer to Android

kian79 — Tue, 27 Feb 2018 04:25:02 GMT

Thanks Martin.

I solved the problem by min and max connection interval to 7.5 and ATT MUT to 150.

#define MIN_CONN_INTERVAL MSEC_TO_UNITS(7.5, UNIT_1_25_MS)

#define MAX_CONN_INTERVAL MSEC_TO_UNITS(7.5, UNIT_1_25_MS)

err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, 150);

RE: BLE UART Slow Transfer to Android

Martin Lesund — Wed, 21 Feb 2018 16:34:54 GMT

Hi Kian79,

Tips from last thread:

You can increase the bandwidth by:

- Send fewer, larger packets, reducing overhead.

-Use the high speed 2 Mbps mode introduced in Bluetooth 5

To increase the ATT MTU you can look at the "ble_app_uart" example and take a look in the gatt_init(), you can see how this is handled for the peripheral side with the function (nrf_ble_gatt_att_mtu_periph_set()). Another tips can be to look at the ATT_MTU Throughput Example and use parts of it as reference. You could also check out this blog describing the different parameters of the example.

Anyway, If you could provide a sniffer log that would also be helpful to see what's happening over the air.