i get a case which stuck at scan pattern presim parallel fail, but serial run pass,
The following are the waveform & fail pattern ATPG good results.
1. parallel presim cell A got mismatch in pink area，（sim = 0， exp=1）
2. fail pattern ATPG ： From this pic ， we can see the D pin of cell A is 100， but simulated value is 000， and mismatch come from cell B，
3. serial presim：
we can see serial result and ATPG is match（cell B get 1 after shift done）
How can I debug the parallel presim mismatch?