Abstract: A security method for preventing accidental or unauthorized writes to a flash memory. According to one embodiment of the present invention, a BIOS program stored in a flash memory array generates a random access code when executed by a processor. A check register stores the random access code and enables write operations to the flash memory array based upon an externally provided access code. In another embodiment, the BIOS program directs the processor to write the random access code to the check register to enable write operations in response to an external write request.
Abstract: A random access interface is provided to a non-volatile, serial memory array. An address multiplexer has an external address connection and a serial address connection. The external address may be of a non-sequential nature, depending on the accessing instruction. Boot data is loaded from the first row of the memory array to a cache register. If a random access mode is enabled during a boot operation, the external address is applied to a data multiplexer that accesses the boot data from the cache register and executes the instructions.