How to config STM32WB55 BLE connect Window Size?

[lbo.1]

When I use an STM32WB55 as a Central to connect to another STM32WB55 acting as a Peripheral, I find via a sniffer that the Window Size in the connection parameters is 3 (3.75 ms). However, when I connect the same Peripheral with a mobile phone, the sniffer shows the Window Size is 1 (1.25 ms). How can I modify this parameter in the STM32WB55?

[Imen.D]

Hello @lbo.1 ,

Try adjusting the connection interval and event length parameters during connection setup. This may affect the timing and window size. 

You can refer to this PM0271, which may help you to update the connection parameters in "6 Bluetooth® LE multiple connection timing strategy" section.

[lbo.1]

Yes, I have attempted to modify the Conn_Interval and CE_Length parameters of the aci_gap_create_connection function, yet the window size remains at 3.75 ms. Is this parameter hardcoded in the BLE protocol stack?