A pattern generator for semiconductor test system for testing a semiconductor
memory
device by generating and applying test patterns. The pattern generator is capable
of freely generating inversion request signals for inverting the read/write data
for specified memory cells for a memory device under test having different total
numbers of memory cells between X (row) and Y (column) directions. The locations
of specified memory cells are on a diagonal line on an array of memory cells in
the memory device under test or on a reverse diagonal line which is perpendicular
to the diagonal line.
