Abstract: A method, system, and product are disclosed for isolating a defect in a memory system by determining in which particular component of the memory system the defect exists. The memory system includes multiple components. The components include a physical memory module, a memory card to which the physical memory module is attached, and a memory controller for controlling the memory card. The memory card includes one or more electrical buffers for driving or detecting the memory signals. The buffers may be used as virtual memory elements. Each component is tested separately in order to identify the defective component with the help of virtual memory system elements. The components are tested by first testing the physical memory module. If the physical memory module passes the test, the memory card is then tested. If the memory card passes its test, the memory controller is tested.

Abstract: A method, apparatus, and computer instructions for backing up data in a nonvolatile random access memory. Selected data is stored in the nonvolatile random access memory in available space in at least one electrically erasable programmable read only memory in the data processing system to form stored data. The stored data is used to restore the nonvolatile random access memory if nonvolatile random access memory becomes corrupted.

Abstract: A recursive on-line wavelet data compression technique which may be used in, for example, a process control network, compresses a stream of data points on-line or in real-time (e.g., as the data arrives or is generated) without requiring the storage of a large amount of uncompressed data. The data compression system includes a data receiver that receives the data points in a sequential manner and a compression tree computation device that determines approximation coefficients and detail coefficients of a multi-layer wavelet compression tree from the received data points. The compression tree computation device determines all of the coefficients of the higher level layers of the compression tree that can be determined after the data receiver receives each of the data points to thereby perform on-line or real-time data compression.