Gustavo Litovsky
EDN (May 04, 2015)
The Bluetooth v4.2 Specification was officially adopted in December of 2014 by the Bluetooth Special Interest Group (Bluetooth SIG) and it brings a host of updates to Bluetooth Low Energy (BLE) or Low Energy (LE) for short. Although no Bluetooth chipset vendor is officially supporting it yet, support will make its way into devices in the next few quarters. There are quite a few updates in the v4.2 specification, and we’re going to go over them and how they can affect your product and design decisions.
LE Data Packet Length Extension
One of the most exciting changes in the specifications is the increase in the Packet Data Unit (PDU) size from 27 to 251 bytes. This is the amount of data sent during connection events. To support the increase requires several updates. One difference is a change in the Header of the Data PDU. This header precedes the payload sent. In the header, the packet length field increased from 5 bits to 8 bits.