Data Transfer between SoftDevice and Android too slow.

RE: Data Transfer between SoftDevice and Android too slow.

awneil — Fri, 01 Mar 2019 15:16:12 GMT

[quote userid="77592" url="~/f/nordic-q-a/44112/data-transfer-between-softdevice-and-android-too-slow/173026"]Settings in the FW (Peripheral)[/quote]

But what settings is the phone actually granting in the actual connection?

Remember that the phone is not obliged to give you those settings!

It is likely to vary from phone-to-phone, and can even vary from one connection to the next on the same phone!

Sigurd — Fri, 01 Mar 2019 14:30:34 GMT

Are you using notification or indication to send the packets?

Could you try to set NRF_SDH_BLE_GAP_EVENT_LENGTH to 320?

It could be that these smartphones only support 1 packet each connection interval when using DLE and max MTU.

A sniffer log would tell us more about what is going on, see this page.

Norman Davidson — Tue, 26 Feb 2019 12:53:10 GMT

Hello,

Please see the answers below

What SDK version are you using ?

15.0.0

What is the connection interval?

Settings in the FW (Peripheral):

MIN_CONN_INTERVAL: MSEC_TO_UNITS(7.5, UNIT_1_25_MS)

MAX_CONN_INTERVAL: MSEC_TO_UNITS(400, UNIT_1_25_MS)

What phone are you using ?

Samsung J3 and Nokia 7.1. Both have the same issues. ie Bluetooth 4.2 and Bluetooh 5

What is the value of NRF_SDH_BLE_GAP_DATA_LENGTH, NRF_SDH_BLE_GAP_EVENT_LENGTH and NRF_SDH_BLE_GATT_MAX_MTU_SIZE in sdk_config.h ?

NRF_SDH_BLE_GAP_DATA_LENGTH = 251

NRF_SDH_BLE_GAP_EVENT_LENGTH = 6

NRF_SDH_BLE_GATT_MAX_MTU_SIZE = 247

Sigurd — Tue, 26 Feb 2019 12:12:11 GMT

Hi,

What SDK version are you using ?

What is the connection interval?

What phone are you using ?

What is the value of NRF_SDH_BLE_GAP_DATA_LENGTH, NRF_SDH_BLE_GAP_EVENT_LENGTH and NRF_SDH_BLE_GATT_MAX_MTU_SIZE in sdk_config.h ?