A hierarchical test control network for an integrated circuit includes a top-level
test control circuit block having a chip access port (CAP) controller. The hierarchical
test control network also has multiple lower-level test control circuit blocks
connected to the top-level test control circuit block in a hierarchical structure.
Each of the lower-level test control circuit blocks are a socket access port (SAP)
controller. Test operation is transferred downward and upwards within said hierarchical structure.