3.2.2.1 Host Tasks

• Command Initiate Task – The purpose of this task is to initiate a variety of commands to establish a connection with the client or target system. It constructs the data packets per the Secure Firmware Upgrade Protocol specifications. The transfer of the firmware image is managed by the Image Reading Task.
• Image Reading Task – This task is engaged in dividing the target firmware into manageable data packets, facilitating the complete transfer of the firmware to the client's device. The segmented data is then forwarded to the Image Encryption Task for subsequent encryption.
• Image Encryption Task – This task is charged with encrypting the segmented firmware data using the internal secure element (ATECC608B). It ensures that the encrypted data, along with the tag and requisite header information, is provided to the Communication Task.
• Communication Task – The Communication Task is tasked with the transmission of data and the provision of responses to the client in the event of any failed transfers. This is executed through the selected communication interface operating in interrupt mode.

The following figure illustrates the flowchart of the firmware upgrade execution on the host.