JPS642157A - Data transfer abnormality detector for data recorder - Google Patents

Abstract

PURPOSE: To immediately detect abnormality when a failure of a timing occurs in course of transferring data by counting and comparing a corrected reference clock and a corrected response clock made by correcting a reference clock and a response clock to be varied equivalently with an identical timing.

CONSTITUTION: The titled detector is provided with a timing reforming part 3 generating the reference clock which measures the time until the response clock is returned for the reference clock, corrects that time difference and of which alteration timing complying with each other is regulated within a fixed time, the equivalent correction reference clock, the response clock and the equivalent response clock, a counting part 4 respectively counting the reformed reference clock and the reformed response clock and outputting the respective discrete values and a relative collation decision part 5 relatively collating the set of discrete values with the optional number of bits among the corresponding bits, successively deciding the coincidence or the discrepancy of them in a data transfer cycle and generating an abnormal signal when the discrepancy occurs. Thus the time delay from the occurrence of the abnormality to the detection can be shortened.

COPYRIGHT: (C)1989,JPO&Japio