Test vector compression method

A method of compressing and decompressing a test vector having a sequence of elements comprising the steps of:

• producing a random sequence of elements having at least a same number of elements as the test vector;
• sequentially segmenting the test vector into segments of the test vector elements, at least one element of the test vector having a don't care value;
• similarly segmenting the random sequence into segments of the random sequence elements corresponding to the test vector segments;
• sequentially comparing each segment of the test vector to the corresponding segment of the random sequence to determine whether corresponding pairs of test vector and random sequence segments match;
• compressing the test vector by inserting different flag values for matched pairs of corresponding segments and for corresponding pairs of segments that do not match;
• and
• decompressing the compressed test vector into a completely specified test vector based on the different flag values.

A method of compressing and decompressing a test vector having a sequence of elements comprising the steps of:

• producing a random sequence of elements having at least a same number of elements as the test vector;
• sequentially segmenting the test vector into segments of the test vector elements, the test vector comprising elements having don't care values;
• similarly segmenting the random sequence into segments of the random sequence elements corresponding to the test vector segments;
• comparing each segment of the test vector to the corresponding segment of the random sequence to determine whether the corresponding segments match;
• sequentially inserting a first flag value into a first sequence for each segment of the test vector that matches the corresponding segment of the random sequence;
• sequentially inserting a second flag value into the first sequence for each segment of the test vector that does not match the corresponding segment of the random sequence followed by inserting the elements of the mismatched test vector segment into the first sequence to create a compressed test vector from the first sequence;
• examining the compressed test vector for first flag values and second flag values;
• sequentially inserting the elements of the random sequence corresponding to each of the first flag values into a second sequence;
• and
• sequentially inserting the elements of the compressed test vector that follow each of the second flag values into the second sequence to produce the decompressed test vector from the second sequence.