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JPark.16
Visitor II
Oct 26, 2020 1:25 AM UTC
Question

How can I change MTU value on my BLUENRG-M2 module

I want to change the MTU value.

As far as I checked through the manual, the mtu value is confirmed through aci_gatt_exchange_config().

I want to change the MTU value set at this time.

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It seems that it can be set when the stack is initialized, but there is no BlueNRG_Stack_Initialization_t variable in the example code.

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I tried changing the ATT_MTU value in bluenrg1_gatt_server.h but it didn't work.

Any help would be greatly appreciated.

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    3 replies

    Winfred LU
    ST Employee
    Oct 27, 2020 5:12 AM UTC

    Take the DK 3.2.1 DTM project for example,

    BlueNRG_Stack_Initialization() is called in DTM_StackInit(), located at DTM_boot.c line 591.

    MTU can be modified in BlueNRG_Stack_Init_params, located at DTM_config.h line 160.

    DKopp.2
    Associate III
    Apr 12, 2023 1:09 PM UTC

    I have run into the same problem. I cannot find BlueNRG_Stack_Init_params. I'm using a X-NUCLEO-IDB05A2 evaluation kit with Nucleo-F303ZE STM evaluation board. Ive downloaded the software pack X-CUBE-BLE1 1.6.2.4. I dont have a config.h file where I have update parameters.

    Any Help will be appreciated.

    Winfred LU
    ST Employee
    Apr 21, 2023 3:23 AM UTC

    BlueNRG-MS does not support data length extension.

    Even though, i think it is possible to have a larger ATT MTU. The frames will be fragmented.

    ATT_MTU is define in bluenrg_gatt_server.h

    I didn't go deep into this. Not sure if modifying this is enough. But it would be a good start.