want to achieve 1-2 Mbps through BLE.

[Mohsin khan]

I am working on project in which i want to read data from sd card and send it to mobile through BLE , I am using ble_nus_send to send data but when i decrease the delay then its giving me error 19 and when i increase delay then it is running smoothly .

Can i achieve something between 1-2 Mbps through ble_nus_Send or have to do with some other approach . 

[Mohsin khan]

Karl Ylvisaker said:

Please provide the logs for all these instances so I may take a look.
Please also include the peripheral's logs for these instances.

nRF Connect, 2021-10-21
nRF Relay (E0:F3:99:D1:24:FB)
I	15:21:45.861	[Server] Server started
V	15:21:45.861	[Server] Creating services...
D	15:21:45.861	[Server callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I	15:21:45.861	[Server] Device with address E0:F3:99:D1:24:FB connected
D	15:21:45.862	[Server callback] Service 0000180d-0000-1000-8000-00805f9b34fb added with status: 0
D	15:21:45.862	server.addService(0000aaa0-0000-1000-8000-aabbccddeeff)
D	15:21:45.870	[Server callback] Service 0000aaa0-0000-1000-8000-aabbccddeeff added with status: 0
D	15:21:45.870	server.addService(0000181c-0000-1000-8000-00805f9b34fb)
D	15:21:45.875	[Server callback] Service 0000181c-0000-1000-8000-00805f9b34fb added with status: 0
I	15:21:45.876	[Server] Database changed
V	15:21:45.886	Heart Rate (0x180D)
- Heart Rate Measurement [N] (0x2A37)
   Client Characteristic Configuration (0x2902)
- Body Sensor Location [R] (0x2A38)
- Heart Rate Control Point [W] (0x2A39)
Unknown Service (0000aaa0-0000-1000-8000-aabbccddeeff)
- Unknown Characteristic [N R] (0000aaa1-0000-1000-8000-aabbccddeeff)
   Client Characteristic Configuration (0x2902)
   Unknown Descriptor (0000aab0-0000-1000-8000-aabbccddeeff)
   Characteristic User Description (0x2901)
   Characteristic Presentation Format (0x2904)
- Unknown Characteristic [I W WNR] (0000aaa2-0000-1000-8000-aabbccddeeff)
   Client Characteristic Configuration (0x2902)
User Data (0x181C)
- First Name [R W] (0x2A8A)
- Last Name [R W] (0x2A90)
- Gender [R W] (0x2A8C)
V	15:21:46.199	Connecting to E0:F3:99:D1:24:FB...
D	15:21:46.199	gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE, opportunistic = true, preferred PHY = LE 1M) (hidden)
D	15:21:46.206	[Callback] Connection state changed with status: 0 and new state: CONNECTED (2)
I	15:21:46.206	Connected to E0:F3:99:D1:24:FB
I	15:21:46.207	MTU changed to: 247
V	15:21:46.222	Discovering services...
D	15:21:46.222	gatt.discoverServices()
V	15:21:46.294	Discovering services...
D	15:21:46.294	gatt.discoverServices()
D	15:21:46.294	[Callback] Services discovered with status: 0
I	15:21:46.294	Services discovered
V	15:21:46.297	Generic Access (0x1800)
- Device Name [R W] (0x2A00)
- Appearance [R] (0x2A01)
- Peripheral Preferred Connection Parameters [R] (0x2A04)
- Central Address Resolution [R] (0x2AA6)
Generic Attribute (0x1801)
Nordic UART Service (6e400001-b5a3-f393-e0a9-e50e24dcca9e)
- RX Characteristic [W WNR] (6e400002-b5a3-f393-e0a9-e50e24dcca9e)
- TX Characteristic [N] (6e400003-b5a3-f393-e0a9-e50e24dcca9e)
   Client Characteristic Configuration (0x2902)
D	15:21:46.297	gatt.setCharacteristicNotification(6e400003-b5a3-f393-e0a9-e50e24dcca9e, true)
D	15:21:46.302	[Callback] Services discovered with status: 0
I	15:21:46.302	Services discovered
V	15:21:46.306	Generic Access (0x1800)
- Device Name [R W] (0x2A00)
- Appearance [R] (0x2A01)
- Peripheral Preferred Connection Parameters [R] (0x2A04)
- Central Address Resolution [R] (0x2AA6)
Generic Attribute (0x1801)
Nordic UART Service (6e400001-b5a3-f393-e0a9-e50e24dcca9e)
- RX Characteristic [W WNR] (6e400002-b5a3-f393-e0a9-e50e24dcca9e)
- TX Characteristic [N] (6e400003-b5a3-f393-e0a9-e50e24dcca9e)
   Client Characteristic Configuration (0x2902)
D	15:21:46.306	gatt.setCharacteristicNotification(6e400003-b5a3-f393-e0a9-e50e24dcca9e, true)
I	15:21:46.594	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-0D-0A-32-32-32-31-2C-32
A	15:21:46.594	"
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,2
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,3
2221,2" received
I	15:21:46.728	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-35-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31
A	15:21:46.728	"221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,4
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,5
2221,2221,2221" received
I	15:21:46.772	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-36-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-37-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32
A	15:21:46.772	",2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,6
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,7
2221,2221,2221,2221,22" received
I	15:21:46.773	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-38-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-39-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C
A	15:21:46.773	"21,2221,2221,2221,2221,2221,2221,2221,89,2221,8
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,9
2221,2221,2221,2221,2221,2221," received
I	15:21:46.774	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-30-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-31-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32
A	15:21:46.774	"2221,2221,2221,2221,2221,2221,89,2221,10
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,11
2221,2221,2221,2221,2221,2221,2221,2" received
I	15:21:46.776	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-33-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32
A	15:21:46.776	"221,2221,2221,2221,2221,89,2221,12
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,13
2221,2221,2221,2221,2221,2221,2221,2221,22" received
I	15:21:46.777	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-34-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-35-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32
A	15:21:46.777	"21,2221,2221,2221,89,2221,14
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,15
2221,2221,2221,2221,2221,2221,2221,2221,2221,222" received
I	15:21:46.778	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-36-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-37-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31
A	15:21:46.778	"1,2221,2221,89,2221,16
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,17
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221" received
I	15:21:46.780	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-38-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-31-39-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C
A	15:21:46.780	",2221,89,2221,18
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,19
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221," received
I	15:21:46.781	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 38-39-2C-32-32-32-31-2C-32-30-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-31-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32
A	15:21:46.781	"89,2221,20
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,21
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,222" received
I	15:21:46.782	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 31-2C-32-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-33-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-34-0D-0A
A	15:21:46.782	"1,22
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,23
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,24
" received
I	15:21:46.783	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-35-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-36-0D-0A-32-32-32-31-2C-32
A	15:21:46.783	"2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,25
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,26
2221,2" received
I	15:21:46.784	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-37-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-38-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32
A	15:21:46.784	"221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,27
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,28
2221,2221,22" received
I	15:21:46.785	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-32-39-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-30-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32
A	15:21:46.785	"21,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,29
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,30
2221,2221,2221,222" received
I	15:21:46.786	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-31-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31
A	15:21:46.786	"1,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,31
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,32
2221,2221,2221,2221,2221" received
I	15:21:46.787	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-33-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-34-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C
A	15:21:46.787	",2221,2221,2221,2221,2221,2221,2221,89,2221,33
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,34
2221,2221,2221,2221,2221,2221," received
I	15:21:46.788	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-35-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-36-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32
A	15:21:46.788	"2221,2221,2221,2221,2221,2221,89,2221,35
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,36
2221,2221,2221,2221,2221,2221,2221,2" received
I	15:21:46.789	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-37-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-38-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32
A	15:21:46.789	"221,2221,2221,2221,2221,89,2221,37
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,38
2221,2221,2221,2221,2221,2221,2221,2221,22" received
I	15:21:46.790	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-33-39-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-30-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32
A	15:21:46.790	"21,2221,2221,2221,89,2221,39
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,40
2221,2221,2221,2221,2221,2221,2221,2221,2221,222" received
I	15:21:46.791	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-31-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31
A	15:21:46.791	"1,2221,2221,89,2221,41
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,42
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221" received
I	15:21:46.792	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-33-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-34-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C
A	15:21:46.792	",2221,89,2221,43
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,44
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221," received
I	15:21:46.793	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 38-39-2C-32-32-32-31-2C-34-35-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-36-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32
A	15:21:46.793	"89,2221,45
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,46
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,222" received
I	15:21:46.794	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 31-2C-34-37-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-38-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-34-39-0D-0A
A	15:21:46.794	"1,47
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,48
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,49
" received
I	15:21:46.795	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-35-30-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-35-31-0D-0A-32-32-32-31-2C-32
A	15:21:46.795	"2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,50
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,51
2221,2" received
I	15:21:46.796	Notification received from 6e400003-b5a3-f393-e0a9-e50e24dcca9e, value: (0x) 32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-35-32-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-32-32-32-31-2C-38-39-2C-32-32-32-31-2C-35-33-0D-0A-32-32-32-31-2C-32-32-32-31-2C-32-32
A	15:21:46.796	"221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,52
2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,2221,89,2221,53
2221,2221,22" received

these are logs of nrf connect while i am connecting with both nrf connect and nrf toolbox .

<info> app_timer: RTC: initialized.
<info> app: 0
<info> app: HRS_C_INIT
<info> app: BAS_C_INIT
<info> app: Heart Rate collector example started.
<info> app: Starting scan.
<info> app: 0
<info> app: peripheral Connected
<info> app: Data length for connection 0x1 updated to 251.
<info> app: Data length for connection 0x1 updated to 27.
<info> app: Data len is set to 0xF4(244)
<info> app: GATT ATT MTU on connection 0x1 changed to 247.
<info> app: Data length for connection 0x1 updated to 251.
<info> app: Initializing disk 0 (SDC)...
<info> app: Capacity: 1902 MB
<info> app: Mounting volume...
<info> app: 
 Listing directory: /
   <DIR>   SYSTEM~1        0  000041C6.TXT   223049  BOOK1C~1.XLS  1051955  GUIDEF~1.PDF  1377436  LATCH-~1.PDF   <DIR>   SALMAN  2906452  HRCOMP.CSV 33563537  ESTTT.CSV 69754908  TESTFILE.CSV 69754908  1.CSV  3145720  HR.CSV<info> app: tempting to set BLE_COMMON_CFG_VS_UUID.
<info> app: Writing to file hr.CSV...
<info> app: data size: 0 bytes
<info> app: File size: 3145720 bytes
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: 4667
<info> app: done
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Data length for connection 0x1 updated to 251.
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Disconnected
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app: Scan timed out.
<info> app: Starting scan.
<info> app: 0
<info> app_timer: RTC: initialized.
<info> app: 0
<info> app: HRS_C_INIT
<info> app: BAS_C_INIT
<info> app: Heart Rate collector example started.
<info> app: Starting scan.
<info> app: 0

These are peripheral logs . 

Karl Ylvisaker said:

Could you detail exactly how you are calculating your achieved throughput, by the way?

 I am just sending data and calculate time my self and self calculating the throughput .

Karl Ylvisaker said:

It could directly influence your throughput if you are only measuring the throughput of your main context, while in reality a lot of the throughput is lost to the UART handler. This is why I mention it. You should make sure that the UART is not receiving any data which it then queues for sending.

No i am not sending any data to uart at the time . 

[Karl Ylvisaker]

Mohsin khan said:

No i am not sending any data to uart at the time . 

Mohsin khan said:

I am just sending data and calculate time my self and self calculating the throughput .

Thank you for confirming this. Reading out the throughput manually will not give the most accurate readings. For accurate readings you should instead have the central close the connection (or disable CCCD) after a given time, and write out the number of bytes it received in the time that the test was running. The timer could for example be started when the first notification is received.

Mohsin khan said:

these are logs of nrf connect while i am connecting with both nrf connect and nrf toolbox .

In the first of these logs it no longer appears that the preferred PHY is updated, so here again you seem to be using the 1 M PHY. In your previous logs there was a PHY update request that was accepted, making the connection use 2 M PHY, this seems to be missing in the latest log.

The last of the two logs seems to be from the central, which is able to connect at first, but then it resumes scanning - are you attempting to connect multiple devices to your central? Could you also elaborate on the section in which the data length is updated multiple times in a row - why is this done?
It also seems like the central is unable to find any other peripherals after the initial connection, and that there is no activity on the initial connection (though I do not see a disconnected message either, so I assume the connection is still going all through the log).
At the end it seems like the device is reset. Did you reset it manually, or did this happen due to an error occurring in the program?

Could you also provide the logs from the peripheral's side?

Best regards,
Karl

[Mohsin khan]

Also one issue is from nrf52840 data sent but it shows on app after a while , What about that issue . 

[Karl Ylvisaker]

If you are encountering a separate issue with the nRF Connect application please open another ticket for this so that the debugging might happen in parallel with the throughput issue while keeping the forum tidy.

Best regards,
Karl