sd_ble_gatts_hvx() error code 0x3401 inS130

[deepu]

Hiii,

I am working on the ble_central_and_peripheral program(s130) in sdk8.1.0 .I could connect the device to the MCP and on clicking enable service we gets the notification.

what actually happens when we click the enable service?? what i have understood is that it writes 0x01 to a particular handle value.

Then we created an android app for our use and assigned a button which when clicked writes 0x01 to the same connection handle.But the output for that was we could get the value for one time ,for that particular instant only and this error message displays "sd_ble_gatts_hvx() error code 0x3401 central.conn_handle 0x3.

So we tested it with MCP after changing the code like ,right after the connection is established we should get the notification .Unfortunately it also gives the same result(we could get the value for one time ,for that particular instant only and this error message displays "sd_ble_gatts_hvx() error code 0x3401 central.conn_handle 0x3)

So there must be something that happens when we click the enable service in addition to writing 0x01 to the handle

How can we solve this ??

regards

[MartinBL]

Hi

The 0x3401 error is the BLE_ERROR_GATTS_SYS_ATTR_MISSING event indicating that some system attributes are missing. This means that you probably haven't enebaled notification of your characteristic by writing to the Client Characteristic Configuration descriptor (CCCD). I am not skilled in Android programming, but I believe there is a method for enabling notifications: setCharacteristicNotification. There are a lot of questions about return code 0x3401 and Ole Morten has a good explanation here.