Amazon FreeRTOS
User Guide

OTA Portable Abstraction Layer

Amazon FreeRTOS defines an OTA portable abstraction layer (PAL) in order to ensure that the OTA library is useful on a wide variety of hardware. The OTA PAL interface is listed below.


Aborts an OTA update.


Creates a new file to store the data chunks as they are received.


Closes the specified file. This may authenticate the file if it is marked as secure.


Verifies the signature of the specified file. For device file systems with built-in signature verification enforcement, this may be redundant and should therefore be implemented as a no-op.


Writes a block of data to the specified file at the given offset. Returns the number of bytes written on success or negative error code.


Activates the new firmware image. For some ports, this function may not return.


Does whatever is required by the platform to accept or reject the last firmware image (or bundle). Refer to the platform implementation to determine what happens on your platform.


Reads the specified signer certificate from the file system and returns it to the caller. This is optional on some platforms.