Maximum notification frequecy

[BLE_Full_Stack]

Hello All,

Chip :  nrf52832

Mobile App : BLE scanner

Requirement : We want to transfer 20 Bytes(or more) at every 8 ms. Is it possible?

I have tested it :

No of Bytes : 12
Connection Interval : 7.5 ms
Data transfer @ 1 sec            : Done, No data loss
Data transfer  @ 500 ms         : Done, No data loss
Data transfer @100 ms          : Done , No data loss
Data transfer @ 40 ms          : Done , No data loss
Data transfer @ 10 ms          : Data transfer was possible, but we were not manage to check it to BLE Scanner, it was stopped.Application is running but i can't see data in BLE Scanner

Please can anyone confirm on this?Is it possible for 8 ms?

[DaleScott]

Hey, I'm not an expert in this area, but doing the math, if connection interval is 7.5 ms and want data transfer complete by 8 ms, that requires 20 Bytes to be transferred in 0.5 ms.  20/0.5x10-3 = 20,000/.5 = 40,000 bytes/sec = 320,000 bps or 0.32 Mbps.

From infocenter.nordicsemi.com/.../nRF52832_PS_v1.0.pdf

"The RADIO contains a 2.4 GHz radio receiver and a 2.4 GHz radio transmitter that is compatible with Nordic's proprietary 1 Mbps and 2 Mbps radio modes in addition to 1 Mbps Bluetooth® low energy mode."

Since 0.32 Mbps is less than 1 Mbps, this suggests to me that the device is designed to handle 20 Bytes in the 0.5 ms window. I would expect it to be limited to less than 1/0.32 x 20 = 62.5 Bytes at the 8 msec point.