Abstract: A mass storage controller includes a packet filter module for receiving a packet containing an updated sector of a remote file allocation table from a host device. The packet filter module is further operable for scanning the updated sector contents to determine their state. The updated sector is written to a local file allocation table of a local device when the state of the updated sector contents match a first state. An original sector of the local file allocation table corresponding to the updated sector is retained when the state of the updated sector contents match a second state.

Abstract: A mass storage controller includes a packet filter module for receiving a packet containing an updated sector of a remote file allocation table from a host device. The packet filter module is further operable for scanning the updated sector contents to determine their state. The updated sector is written to a local file allocation table of a local device when the state of the updated sector contents match a first state. An original sector of the local file allocation table corresponding to the updated sector is retained when the state of the updated sector contents match a second state.

Abstract: The specification discloses a digital/analog signal analyzer for an electromagnetic surveillance system. Included is a notch filter having a switched capacitor filter controlled by a phase lock loop for nulling a time-varying driving frequency from the received signal. The analyzer further includes structure for digitizing the received signal and for implementing a recursive filter to enhance digital feature extraction. The recursive filter in turn includes structure for delaying a read address for subsequent use as a write address to facilitate the rapid updating of data in memory. Also included is a digital-to-analog converter assembly having a pair of piggy-backed digital-to-analog converters to produce an analog signal dependent upon both a mantissa and an exponent of a digital number in scientific notation.