GATT Server - Characteristic Max Size

[briandunham]

Hello Mike,

I have a GATT client that is subscribed to a characteristic. That characteristic is configured in the GATT server to have a size of 255 bytes. But when my GATT client receives a OnCharacteristicChanged notification, the length is only 20 bytes. Is there a way to change this default MTU to a bigger size?

[Mike Petrichenko]

Unfortunately no, it is not possible on Windows platform. However if all is confugured correctly on a server side Windows always changes MTU size automaticaly to the server specified value. Also there can be dongle's limitation.

[briandunham]

Thank you for the clarification. I was able to find a "set_max_mtu" function in other API that we're using for the GATT server. Which allowed my WCL application in Windows to automatically adjust to the new MTU value.