How to send large data through BLE notification using nrf52832 over Uart Ble

[Manjunath K S]

I am using Uart Ble example of sdk , i want to write to Tx without UART can u please help me do it

i actualy want to send accelerometer data which is of size 40kb after aquistion.

[Einar Thorsrud]

Hi,

I am not sure exactly what you are asking about, so I will giv you a few hints about how to transfer large amounts of data as fast as possible, since that seems to be what you are after. Please elaborate and specify if you need more specific advice later.

To achieve high throughput, you should try to optimize the following:

• User long packets.
• Use long connection events and connection intervals that match (not too short).
• Use notifications.

You can refer to the throughput example in the SDK. You can also adapt the BLE UART example since you allready mentioned it (it was not clear to me if you wanted to not use the NUS service, or just did not what to use physical UART).

[Manjunath K S]

my actual problem statement is:

I am collecting tri axial accelerometer data with sampling rate of 1600 samples/sec,after the acquisition of 4 seconds data,

about 6 bytes per sample  about 38.4 Kb i need to transfer this data Over Ble to raspberry Pi model 3B.

If u can help me at raspberry pi end also it will be great which i am still searching.

How should i proceed.

can i use Ble Nus service for this.

[Manjunath K S]

can u please help me with this issue

[Einar Thorsrud]

Hi,

There is nothing preventing you from using NUS with Linux (RPi). Nordic does not provide any examples, but you can make yourself or refer to some other customers code, such as this (I have never tested it).

[Manjunath K S]

I have 40 kb of data  i need to send, and what i thought was using notification by creating a timer, which will be started as soon as device gets connected, in the timeout handler i will convert every data to string using sprintf  7 send in that for loop, which will be written inside timeout handler, but i am not able to receive all the data y.

or what should i do to achieve this in Uart ble example project , please help me ASAP.