STM32WB55RGV6 What is the maximum payload per notification (BLE server)? How do I need to modify the program？

[Lep]

I want 120bytes per notification,

I want 120bytes per notification, but I can only reach 20bytes with stm32cubemonitor-rf monitoring.

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The following picture is what I mainly modified in the program：

Am I going wrong somewhere?

 

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[Remy ISSALYS]

Hello,

The maximum payload per notification is 251 bytes without fragmentation and you can reach 512 bytes with fragmentation mechanism.

After the connection you should use aci_gatt_exchange_config command to perform an ATT MTU exchange procedure in order to be able to send notification with size near to ATT MTU value set in app_conf.h

Best Regards

[Lep]

Thanks for your help.I can transmit notifications of 120 bytes. Now I have a new problem, when I try to notify of 240 bytes, I can see the data with nrf connect on the mobile phone, but not with stm32cubemonitor-rf. In the program of BLE_TransparentModeVCP, I only changed ATT_MTU_MAX (245), do I need to do anything else?