Automatic selective retest for multi-site testers

A multi-site automated test system, comprising:

• a handler coupled to a contactor comprising a first plurality of contact sites and a microprocessor comprising controller coupled to said handler and contactor;
• said microprocessor running stored code, said code comprising:
• (a) code for loading a first plurality of semiconductor units from a batch of semiconductor units into said first plurality of contact sites;
• (b) code for simultaneously testing said first plurality of units using a test program to determine bin information for each of said first plurality of units, said bin information defining each of said first plurality units being a passed unit or a reject unit;
• (c) code for offloading said passed units from respective contact sites of said first plurality of contact sites to create vacant contact sites while keeping said reject units at respective contact sites of said first plurality of contact sites;
• (d) code for loading untested units from said batch to fill said vacant contact sites, and
• (e) code for simultaneously retesting said reject units and testing said untested units using said test program.