9.4 Device Firmware Upgrade Over Zigbee Link

Designers and providers of embedded wireless systems continue to be challenged by the rapid evolution of the ZigBee® standard. The continuous evolution of the standard requires that these systems must be made future- proof, that is, the system engineers must design them to be easily upgraded systems to the next version even after the system has been deployed. The ability to upgrade networks also depends on the individual devices having enough hardware resources to accommodate the next version of the specification. But even when these hardware resource requirements are met, there still must be a defined and interoperable mechanism for efficient over the air upgrade.

The over-the-air upgrade support in ZigBee networks is covered by the Over-the- Air Upgrade (OTAU) Cluster specification. The OTAU functionality relies on the use of standard ZigBee data transfer and network management facilities to transfer firmware images to any node on the network. The standard covers on air message exchange, but leaves the details of the architecture and implementation up to the vendor. This guide outlines the Microchip architecture and implementation of over-the- air upgrade and describes how to add over-the-air upgrade support to Zigbee applications. The guide also introduces PC side tools for initiating OTAU and explores practical considerations in performing a network upgrade.