A condenser microphone comprises a substrate, a vibratile diaphragm and a back plate. The methods include subjecting a silicon-on-insulator structure to the semiconductor process, precipitating metal contamination in the structure and delineating the metal contaminants. The memory map stores information to identify a memory address range to be associated with a memory. An error correction code is used to check the data but the best portions of the two or more firmware copies stored in the flash memory are used to reduce the need to use ECC.