Abstract: There is disclosed herein an apparatus for automatic monitoring of numerous high speed drill spindles on a numerically controlled drilling machine for purposes of immediate detection of the absence of drilling by a particular spindle because of a broken drill bit. The apparatus detects the absence of drilling, interrupts the automatic cycle of the drilling machine and alerts the operator. Power dissipation in each drill spindle motor is compared just prior to entry of the drill bit into the workpiece and after entry if any. If power dissipation increases above a predetermined threshhold level for all spindles, no interrupt is generated. If power dissipation does not increase in one or more spindle motors, comparator circuits alert a digital processor which interrupts automatic operation of the drilling machine and alerts the operator. Such a system eliminates the expense and error of human visual monitoring and generation of expensive scrap improperly processed before discovery of the broken bit.

Abstract: This relates to an apparatus for performing single error correction, double error detection of binary words, each section of the apparatus processing one byte of raw data. Each section includes first logic means for producing a first plurality of intermediate sector matrix parity outputs. A second logic means receives one of the first plurality of intermediate sector matrix parity outputs and a second plurality of intermediates matrix parity outputs from other sections and generates therefrom a syndrome signal. A third logic means receives this syndrome signal and syndrome signals from other sections and generates therefrom the corrected data bits.

Abstract: This relates to a method and apparatus for testing printed circuit boards. The printed circuit board to be tested is placed on a metal plate and covered with a thin plastic film. The plastic film is coupled to the metal plate to form a substantially air-tight chamber occupied by the printed circuit board. A vacuum is then created in the chamber to secure the printed circuit board. A capacitance meter has a first terminal coupled to the metal plate and a second terminal coupled to a probe which is used to puncture the plastic film to make contact with electrical interconnects on the board.

Abstract: This relates to an apparatus and method for providing an accurate data group to the instruction buffer of a data processing system.The data group is simultaneously applied to the instruction buffer and to the error correcting apparatus. After analysis of the data group in the error correcting apparatus, the operation in progress is aborted if an error has been detected, and the error is not correctable. If correctable, the correct instruction data group is applied to the execution unit. If no error is detected in the data group, utilization of the data group proceeds uninterrupted.Two, three state busses are employed. The first three state bus is used to transmit memory data to the error detection and correction (EDAC) circuitry, to transmit corrected data from the (EDAC) circuitry and to the data output circuits and to transmit input data to the memory.

Abstract: This relates to an apparatus for converting raw data into GCR data and for controlling the recording of GCR data on magnetic tape. An ordered series of instructions is stored in a first programmable read only memory (PROM). A second PROM contains a special character table and a code conversion table, and receives raw data. A third PROM stores addresses which are used to access the second PROM and are indicative of whether raw data is to be converted or a special character is to be generated.