Abstract: A consumer electronic apparatus includes at least a clock, and in some cases a microprocessor, which produces data, such as time-of-day or control parameters, which are stored in volatile memory. A power failure can cause this data to be lost. The data are stored in nonvolatile memory according to an algorithm during normal operation, so that they are available after a power failure. In one version, the parameters are stored at fixed intervals. In another version, the parameters are stored in response to a change. In yet another version, the parameters are stored in a manner which is distributed among plural memory locations to extend life.