Abstract: A digital tester includes a digital data pattern aligner. The digital data pattern aligner includes an alignment pattern source, a data shifter, and a data comparator. The alignment pattern source sends an alignment pattern to the comparator in a data stream. The comparator samples the data stream and compares the samples to a copy of the alignment pattern. The shifter shifts the data in the data stream so long as the comparator detects no match between a data stream sample and the copy of the alignment pattern. When a match is detected, the pattern source and the comparator are in alignment and other data, such as test patterns, may be sent to the comparator or associated components.

Abstract: A data shifter selects data from a plurality of data blocks to effectively “window” data contained within the blocks. A second stage of shifting may be implemented by selection among the resultants of the windowing step. Such a shifter may find use in a data aligner.

Abstract: A digital tester includes a digital data pattern aligner. The digital data pattern aligner includes an alignment pattern source, a data shifter, and a data comparator. The alignment pattern source sends an alignment pattern to the comparator in a data stream. The comparator samples the data stream and compares the samples to a copy of the alignment pattern. The shifter shifts the data in the data stream so long as the comparator detects no match between a data stream sample and the copy of the alignment pattern. When a match is detected, the pattern source and the comparator are in alignment and other data, such as test patterns, may be sent to the comparator or associated components.

Abstract: A data shifter selects data from a plurality of data blocks to effectively “window” data contained within the blocks. A second stage of shifting may be implemented by selection among the resultants of the windowing step. Such a shifter may find use in a data aligner.