Removable memory devices, such as flash memory cards, usually implement a file system for managing directories and files, including system files. System files typically contain firmware (i.e., “flashware”) instructions for initializing the flash memory card, and for interfacing a host electronic device with a memory space in a non-volatile memory. Occasionally, firmware instructions are upgraded to correct “bugs” and other deficiencies.
But a common drawback to conventional techniques for upgrading firmware is that a loss of power during the upgrade process could result in data corruption. For example, firmware is frequently corrupted when the flash memory card is disconnected from its power and/or data source while new data is being written to it. Encryption, when used, exacerbates the corruption. Typically, the corruption of the firmware is irreversible, which renders the flash memory card inoperable. The user has little choice but to ship the flash memory card back to the manufacturer (or some third party) to recover its functionality. But a drawback to restoring the firmware at the manufacturer is that the application data stored in the flash memory is usually erased during traditional firmware recovery processes.
Other traditional approaches to upgrading firmware have aimed to reduce the impact of interruptions during the upgrade process. While these other approaches are functional, they appear to be suboptimal in that some approaches upgrade firmware in tandem with memory functionality. As such, these approaches do not sufficiently immunize the user and/or the functionality of the non-volatile memory (and its application) from power disruptions during firmware upgrades and data recovery mechanisms.
It would be desirable to provide improved techniques and structures that minimize one or more of the drawbacks associated with conventional techniques for upgrading non-volatile memory and recovering firmware, for example, in a removable memory device.