Browse Prior Art Database

Error Detector

IP.com Disclosure Number: IPCOM000096654D
Original Publication Date: 1963-Sep-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 43K

Publishing Venue

IBM

Related People

Oeters, HR: AUTHOR [+2]

Abstract

Errors in incoming data are detected. Such data is regularly sampled and stored in a data bit trigger prior to use by a data processing system. As shown in the waveform drawing, by comparing the value of the data at the sample time with the value at the time of the last transition, pulse noise and signal failure errors are detected.

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Error Detector

Errors in incoming data are detected. Such data is regularly sampled and stored in a data bit trigger prior to use by a data processing system. As shown in the waveform drawing, by comparing the value of the data at the sample time with the value at the time of the last transition, pulse noise and signal failure errors are detected.

Convert circuits C split binary input signals, entered on one input line, into signals on two complementary output lines. Delays are indicated by D1, D2 and D3.

Transitions are detected by comparing, in Exclusive-Or 1, the current value on the data line with a previous value stored in a last data trigger. Whenever a data transition is detected, the expected data value is placed into the next bit trigger by transferring to it the contents of the data bit trigger inverted.

Subsequently, at sample time, the actual data value is placed into the data bit trigger and compared by Exclusive-Or 2, with the expected value in the next bit trigger. The next bit trigger is then initialized by setting it to the value of the data bit trigger.

A data error is indicated if a 1 bit is expected and a 0 bit appears on the data line, or when a 0 bit is expected and a 1 bit appears.

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