Abstract: An array processor is described consisting of a plurality of modules connected together in rows and columns. Each module has at least one special terminal which, as well as providing a connection for transfer of data between adjacent modules, also provides an output which is combined with similar signals from the other modules in the same row, to form a row response signal. Alternate modules in each row are rotated by 180.degree. with respect to each other, so that the special terminals on adjacent modules are connected in pairs. This reduces the complexity of the circuits for forming the row response signals.

Abstract: A binary adder circuit which, in response to a mode selection signal, is forced to operate as if two of its inputs were equal, irrespective of the actual value of those inputs. In this condition, the circuit acts effectively as a connector, coupling two of its inputs direct to the sum and carry outputs. The invention is useful in a circuit arrangement for performing adding and shifting operations.

Abstract: A binary adder has a switching circuit connected to one of its inputs. When activated by a mode selection signal, the switching circuit forces two of the adder inputs to receive the same input signal. In this condition the adder acts effectively as a connector, coupling two of its inputs direct to the sum and carry outputs. The invention is useful in an array processor, for performing additions and shifting operations.

Abstract: A system for displaying data, especially graphics data in color or grey scale on a raster-scanned display device. The information to be displayed is supplied in a coded representation in which a run of a new display value is represented by a transition code element representing at least the display value of the first picture element of the run, followed by a run-length code indicating the length of the segment of picture elements following the element or elements represented by the transition code. The coded representation is decoded to drive a display device.

Abstract: A platen assembly for feeding and holding single or multi-layer record media (forms) for printing thereon, particularly useful in connection with a matrix type printer of a point-of-sale terminal. This assembly comprises one of a pair of feed rollers pivotally mounted so as to yieldingly engage and hold both sides of the record media, while a platen yieldingly engages and holds the record media against guides which determine the gap between the matrix head for proper operation of the printer wires. For line-by-line printing, the platen is first disengaged from the record media while the power feed rollers move the record media the required distance before the platen again engages the media.

Abstract: A data processing unit in which the clock speed is selected to match the access times of the store units connected to it. This is achieved by means of a special terminal on each store unit, this terminal being internally grounded if the unit is of a slow access type, and open-circuited if the unit is of a fast access type.

Abstract: A fastening device is disclosed for joining two members, for example tubular members, together, one of the members having a recess in an end which is to abut the other member. The device includes wedge elements which are moved relative to one another to engage opposed internal walls of the recess in the one member so that by attaching one of the wedge elements to the other member the members are secured to one another. Deformable links interconnect the wedge elements to initially retain the elements in their operative positions but to subsequently deform when relative movement is produced between the elements.

Abstract: A pipelined data processing system having n processing stages, each of which is under the control of a central microprogram. Each microprogram instruction is decoded to produce n control signals, one for each processing stage. Microprogram start addresses are generated by combining information from the latest n program instructions received. Thus, each microprogram sequence implements a combination of phases of successive program instructions. A flag register is used to store relatively static control information, and effectively provides an extension of the microprogram instruction.

Abstract: Hash-coding storage arrangements are known which are capable of storing data values efficiently and permitting rapid testing of whether a given data value is stored. However, such arrangements may produce erroneous outputs. The invention reduces or eliminates these erroneous outputs by providing a further store (which may itself be a hash-coding storage arrangement) which identifies the erroneous outputs, and is used to suppress them.

Abstract: An electrical connector including a rigid core having spaced shaped grooves each mounting an elongate resilient member. A flexible strip of insulating material is wrapped around the core. A plurality of spaced apart conductive strips is provided on the strip so that the strips extend circumferentially around the core.

Abstract: A data processing system is disclosed in which a store has a plurality of pairs of storage locations. An indicator is provided for each location pair to indicate which location of the pairs is to be used for read and write accesses. The indicators are each set to indicate that after a write access to a pair of locations, read accesses are to take place to the location of the pair currently indicated for write accesses and periodically, for example at the end of a sequence of instructions, the indicators are set to indicate that write accesses are to take place to the opposite location of the pair to that which is currently indicated for read accesses.

Abstract: A method of forming very small diameter holes in a flexible substrate by coating both sides of substrate with metal layers; etching layers and substrate at places where holes required, removing small ring of the metal layers surrounding holes to remove any overhang of metal; and plating walls of holes and providing electrical conduction with said layers.

Abstract: In a pipelined data processor, each processing stage is provided with its own copies of relevant machine registers. Whenever a processing stage updates a register, it sets a flag. The flags and register copies are shifted along in step with the flow instructions down the pipeline. These flags are used to control multiplexers which ensure that each stage is provided with the most up-do-date copy of each register, taking into account any updates by succeeding stages.

Abstract: A method of making flexible radially compressible tubular electrical connectors involving producing a hollow elastomeric core in a tube of precise dimensions, and then removing circumferential strips of the tube to leave separated conductive rings and strips which provide the electrical connector elements of the connector.

Abstract: Speech synthesizing apparatus is provided in which different sounds are required for a plurality of channels. The channels are polled in turn on a cyclic scanning basis, the scan for each channel occupying a channel sampling period during which an instantaneous value is generated for the amplitude of a voiced sound component. Values representing instantaneous amplitudes of each of a plurality of unvoiced sounds are separately generated in turn during the period occupied by the scanning of all the channels and these values are stored. A selected one of the unvoiced sound values is extracted from the store as required for a particular channel during the sampling period for that channel, so that an updated value for the unvoiced sound is available on each occasion that that particular channel is sampled. The voiced and unvoiced sound values are then combined during the appropriate sampling periods. The required sound combinations are specified by parameters expressed in digital form for each channel separately.

Abstract: A method of forming buried regions in a printed circuit substrate in which; a first layer of doped silicon oxide is deposited on the substrate, a pattern of apertures is produced in this layer and a second layer of differently doped silicon oxide is deposited to fill in apertures. The first layer silicon dioxide acts as a mask to the doping material so that when the two layers are subjected to a common diffusion step both doping materials are driven into the substrate, with the second layer doping material restricted to the regions of the apertures.

Abstract: A hierarchical data storage system comprises a main store and a smaller, faster slave store containing data currently required for processing. The memory system responds to a store access command to retrieve an item of data. In addition, for certain types of store access command, the system performs a look-ahead action to ensure that the slave store is loaded with another data item which forms part of a possible sequence. In certain cases, a test is made to determine whether the possible sequence is in the ascending or descending direction, and the look-ahead access is then made in the appropriate direction.

Abstract: A graphic display apparatus in which the data to be displayed is stored as two types of data word, one type representing groups of increments of beam displacement of a beam displacement tube and the other representing differences between the data constituting a raster line and that of next succeeding line. The data for each line formed from the first type of words is temporarily stored in a line store while being displayed on the tube. The contents of the line store are modified according to any second type words received during the display period so as to convert the stored data into that for the next line to be displayed.

Abstract: Speech synthesizing apparatus is provided using digital coded values specifying parameters of a sound to be reproduced. The apparatus has a voiced sound generator using digital values specified by input parameters to represent three formant waveforms respectively which are sampled at substantially constant intervals, the parameters each expressing in relation to the sampling interval the frequency of the formant concerned. At each sampling, the input parameters are arranged to derive for each formant waveform respectively a value representative of the instantaneous amplitude of that waveform in relation to the others, the three values obtained then being combined to produce a resultant value representing an instantaneous amplitude output of a voiced sound component waveform. This output waveform is subjected to modification by attenuation and the addition, if required, of an unvoiced sound component before being passed through an analogue converter to a sound reproducing transducer.