@zmrzli Make sure you are sending the correct length and AD types according to the ADVERTISING AND SCAN RESPONSE DATA FORMAT (page 2081 on the Bluetooth 4.2 Core Spec - you can access the specification here https://www.bluetooth.com/specifications/adopted-specifications ). If you're looking to use BLE advertising packets to send your data you probably want to use AD type 0xFF (Manufacturer Specific Data) followed by the 2 company identifier octets. So your format should be 1 byte length + 0xFF + <2 bytes company identifier> + your data then filled with 00 until the 31 byte limit. You can't read improperly formatted advertising data.