The intelligence and complexity of sensors and actuators is constantly increasing, and not just in the context of Industry 4.0. Even the smallest sensors today have a powerful microcontroller and several thousand lines of software code. Firmware updates may be required from time to time, for example to enable new functionalities or for newly supported profiles that were not yet known at the time the device was developed. To meet these requirements, the IO-Link community has specified a manufacturer-independent firmware update profile.

The firmware update profile is currently being implemented by various manufacturers of IO-Link devices and uses the newly developed BLOB transfer (Binary Large Objects) for the transfer of large amounts of data. This will make firmware updates easier and faster in the future.

The manufacturer of the device provides a special file (*.iolfw) for the firmware update which, in addition to the actual device software, also contains additional information, e.g. for verification or information for the customer. The IO-Link profile can also be used to develop tools for parameterizing the master for the firmware update. The user can use such a tool to open the file provided and start the update process. The tool checks whether the firmware and the device are compatible. If the authentication was successful, the tool switches the device to bootload mode and starts the actual transfer and storage of the new software in the device. At the end of the process, the status of the update is displayed and, if the update is successful, the device is restarted so that it can then be used with the new functions in the system. The update of a typical device should take less than 1 minute.

In order to guarantee a high level of security and simplicity at the same time, the profile was developed according to strict specifications. For example, new firmware images may only be written to compatible devices. In addition, the software update must work via standard IO-Link wiring in the field. This means that no special IO-Link masters are required. Last but not least, the new software can only be written to the device - it is not possible to read it out. And if something really goes wrong when transferring the new software, each device has a small bootloader to start the process a second time.