Abstract: A method and circuit for a high speed interface that enables the integration of several Content Addressable memories into a larger, Combined Content Addressable Memory with only an insignificant delay in the original response time of the individual memories. The interface provides connections to the Bus system only and no connection between different CAM devices of the system is needed, whereby the combination of one CAM and one CAM interface in a single device, such as a chip is enabled. Such chips may be used as modules for increasing the CAM Memory by directly attaching them to the Bus System without any additional interface, as known for standard memory chips such as RAM. The inventive interface may also be used for creating a hierarchical structure within a CAM device by dividing the memory cells in groups, each group being interfaced to the larger combined CAM device via an interface according to the invention.

Abstract: A high-resolution position sensor device for use in precise positioning of servomechanisms, by providing increased resolution using of an encoder mounted on the shaft of a motor, which produces transition pulses through a light-sensitive arrangement using a photodetector. Each time the pulse makes a transition because the groove of the encoder wheel has passed, a reset signal is produced which resets to zero the number of clock pulses which have been measured for that interval between the transition pulses. The transition pulses and the time between them changes with changes in motor speed, while the system clock pulse rate remains fixed. The invention provides a more accurate position sensor, which operates by generating more transition pulses than the encoder itself actually generates. If the encoder produces transition pulses at a given resolution, the sensor device produces output pulses having a higher resolution.

Abstract: A CAM memory for searching Words of variable size, that may be divided into Comparison Units of different sizes, each containing a string of Subwords. The positions of the Subwords at both ends of a Comparison Unit are selected by means of Command Signals. Consequently, words of the data to be searched of any size may be stored contiguously in the Words of the Memory such that all of the Memory may be used for storage and searching. The number of Searching cycles and the time required for finding the position of a word of data is significantly reduced. The Match Signal from a Subword is put out as a Word Match only where the whole string of preceding Subwords of the same Comparison Unit have set Match Signals and the subsequent Command Signal has been set.

Abstract: A high-resolution position sensor device for use in precise positioning of servomechanisms, by providing increased resolution using of an encoder mounted on the shaft of a motor, which produces transition pulses through a light-sensitive arrangement using a photodetector. Each time the pulse makes a transition because the groove of the encoder wheel has passed, a reset signal is produced which resets to zero the number of clock pulses which have been measured for that interval between the transition pulses. The transition pulses and the time between them changes with changes in motor speed, while the system clock pulse rate remains fixed. The invention provides a more accurate position sensor, which operates by generating more transition pulses than the encoder itself actually generates. If the encoder produces transition pulses at a given resolution, the sensor device produces output pulses having a higher resolution.

Abstract: A memory system includes an array of memory cells with a Bit Mask circuit provided in each memory cell. The memory system also includes a bus circuit with a set of Address Bus lines, a set of Data Bus lines, a set of Origin Bus lines and a set of Control lines, each memory cell being connected to each of the sets of lines. In a first operating mode, the system stores data applied on the Address Bus. In a second operating mode, a memory cell having a position defined by the Address Bus outputs on the Data Bus the data stored in that cell. In a third operating mode, the searched data is applied on the Address Bus and each memory cell with matching data outputs on the Data Bus a value representing the Address of the memory cell. However, the cell address is output on the Data Bus only where the position of that particular memory cell is the closest, in a predefined direction, to the data set on the Origin Bus among all the cells with matching data.

Abstract: A method and circuit for a high speed interface that enables the integration of several Content Addressable memories into a larger, Combined Content Addressable Memory with only an insignificant delay in the original response time of the individual memories. The interface provides connections to the Bus system only and no connection between different CAM devices of the system is needed, whereby the combination of one CAM and one CAM interface in a single device, such as a chip is enabled. Such chips may be used as modules for increasing the CAM Memory by directly attaching them to the Bus System without any additional interface, as known for standard memory chips such as RAM. The inventive interface may also be used for creating, a hierarchical structure within a CAM device by dividing the memory cells in groups each group being interfaced to the larger combined CAM device via an interface according to the invention.

Abstract: A method and circuit to be applied in content addressable memories for finding a word with the longest match to the searched data. A word of data is stored in each memory cell, the word of data is composed of a group of sub words in a predefined order and each sub word is composed of one or more bits of memory.