MTU is set to 527

[ericlangel]

Operating System

Windows 10

IDE version

Arduino 1.8.19

Board

Feather nrf52832

BSP version

V1.2

Sketch

Throughput.ino

with Debut output of MTU Size

data_mtu = Bluefruit.Connection(0)->getMtu() - 3;
Serial.print("MTU Size: ");
Serial.println(data_mtu);

What happened ?

MTU Size return Value is 527

My Buffer Size is Set to 247 because i thought that 247 is the absolut maximum.
So the whole stack crash (dosesnt advertise any more after some notifies with 527 Bytes)

Now my Question: Why in Hell does the Bluefruit Stack accept a MTU Size of 527?

How to reproduce ?

Use Throughput Example with Windows BLE Library "Bleak"

Debug Log

MTU Size: 524

Screenshots

No response