Patent ID: 8566561
Filing Date: 2013-10-22
Classification: G05B

Abstract:
1. A method of retaining a plurality of data objects in memory in an industrial controller having both a volatile memory and a non-volatile memory, comprising the steps of: classifying each of the data objects as a static data object or a dynamic object, wherein each static data object is changed at a frequency less than a preselected threshold frequency and each dynamic object is changed at a frequency greater than a preselected threshold frequency; storing each static data object in the non-volatile memory; allocating an address in the volatile memory for each dynamic data object and for at least a portion of the static data objects; updating the dynamic data object in the volatile memory when each dynamic data object changes; for the portion of static data objects having the addresses allocated in the volatile memory, tracking the change of the static data object in non-volatile memory and updating the static data object in the volatile memory when the static data object changes, wherein tracking the change of the static data object in non-volatile memory occurs prior to updating the static data object in the volatile memory; copying a present value of each dynamic object in the volatile memory to the non-volatile memory when power is removed from the controller.