Abstract:
This specification discloses a binary counter with two channels each consisting of a binary counter with ripple carry. Both channels store the same binary number, and to advance the count, a pulse is first applied to the input to one counter and thereafter applied to the input of the other counter. The output of each stage in one counter is Exclusive Ored with the output of the same stage in the other counter. The results of this Exclusive ORing is analyzed with additional logic circuitry to determine if the counts in the two channels are or are not equal. If they are not equal the analysis determines which of the counters contains the higher count, and if the difference in the counts is greater than one. This information is then used to find which of the channels is in error and whether the error is a transient error or an error resulting from a hard failure in one of the channels.
Abstract:
An error correction and detection circuit includes a modular encoder that provides the minimum number of check bits for encoding a particular number of data bits. Means is provided for combining several units to produce the minimum number of code bits when a larger data word is to be encoded. A storage hierarchy system using this error correction circuit is also disclosed.
Abstract:
A shift register store and associated controls store randomly entered classes of data records and output the data records on request by specific class in the identical order in which the records of the class were entered into the register. Records are compacted in the register so that no blank character codes exist between records. Blank codes exist only at the end of all valid records on the register. The register and controls and particularly useful in proof/inscribe/sort apparatus of the type used in bank proofing departments to permit the economic use of only one tape advance/print mechanism to produce specific class tapes for a multiplicity of sorter pockets, the documents sorted into each pocket being of the same class. The register and controls are useful in other environments, e.g., to buffer data from a plurality of terminals in a teleprocessing system from key-to-tape (or disk) entry systems, from multi-station inquiry and data collection systems, and in message concentrator application.