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Code Checking and Comparing

IP.com Disclosure Number: IPCOM000096495D
Original Publication Date: 1963-Jun-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 56K

Publishing Venue

IBM

Related People

Janus, W: AUTHOR

Abstract

For the purpose of making a comparison or parity check of a 7-bit code, two groups of cores each comprising two cores A and B are employed. For the even parity check the groups of cores are wired so that in each group 1 and 2 an output signal is produced only in the presence of an odd bit combination, odd + odd = even.

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Code Checking and Comparing

For the purpose of making a comparison or parity check of a 7-bit code, two groups of cores each comprising two cores A and B are employed. For the even parity check the groups of cores are wired so that in each group 1 and 2 an output signal is produced only in the presence of an odd bit combination, odd + odd = even.

Such a wiring arrangement is for checking the 1, 2, 4, 8 bits in the 1 group, the 2 group of cores serving to check the A, B and C bits. The wiring of the latter group has an additional line by which the device is used for odd check operations. In this case, a signal is also applied to the odd line at each of the bit times.

The output signals of the groups of cores are applied through And's and an Or to the error trigger T which effects a Mod 2 count of the input pulses. In its 1 position, the error trigger T supplies a signal to switching circuit D. This is responsive only to pulses, the time duration of which is larger than the time interval between the corresponding sample pulses 1 and 2.

In this manner, error trigger T is set to its 1 position by the sample pulse 1 if, for example, an odd bit combination is present in the 1 core group. It is reset before an error alarm is signaled by switching circuit D, if an odd bit combination is present also in the 2 core group. If an odd bit combination is present in only one group of cores. the error trigger remains in its 1 position. It initiates the alarm in a device, not sho...