Firmware Updates
Installation of a binary file to the device is supported, if the device manufacturer supplies the code to install the flash updates. There are two basic locations where a BIN file can be installed. In both situations, it is the OEM that knows the hardware and how to install the binary file onto the device.
XIP Flash
The OEM executes code directly from flash and therefore, the image cannot be directly saved to flash without putting the system into a safe state. A safe state would be to:
- Halt all operations.
- Have RAM-based code that knows how and where to copy the flash.
- Have safety guards in place to protect against partial or fatal updates.
Non-XIP Flash or other storage
The OEM executes code out of RAM. The OS image is stored in a store of any kind and when the device boots, the image is copied to the RAM directly or decompressed and copied to RAM. This situation allows the OS to be fully running when an update occurs. Some steps still have to be taken to ensure that the device is in a usable state after the update occurs. The OEM should have safety guards in place to protect against partial or fatal updates.
See Also
Last updated on Thursday, April 08, 2004
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