Client writing a value to GATT write attribute

Hello @Community member​ 

Could you please precise the STM32 product you are using? STM32WB ..? Which type of server? Do you mean using host stack subsystem of Bluetooth? If so, I suggest to refer to STM32 Bluetooth Low Energy - stm32mcu

STM32WB55CU6 custom board as client and ESP32 as server, Connection between client and server done, Now i need to write a value to server from client

I am using GAP connection and GATT attribute method

Hello @Community member​ 

You can refer to AN5289, section 6 Step by step design of a BLE application. Table 6. to choose the API

Thank you,

I have followed this document to establish a connection, but in the document, I didn't understand how to write attribute value to the server from the client

Hello,

To write a value from your client to your server, in case of write without response you can use ACI_GATT_WRITE_WITHOUT_RESP command and in case of write with response you can use ACI_GATT_WRITE_CHAR_VALUE command. You can look BLE_p2pServer/BLE_p2pClient examples which allow to establish a connection and exchange information between two STM32WB boards.

Best Regards