Parallel test mode for multi-core processors

摘要

An embodiment of the present invention is a technique to provide a parallel test mode for multi-core processors. A test access port (TAP) in a first processor core generates a first test data output (TDO) from a first test data input (TDI) or a first delayed TDI according to a TDO select bit. The first delayed TDI is clocked by a test clock (TCK). The first processor core has a first core circuit. The TAP generates a phase select word. A clock generator generates a clock signal synchronized with the TCK and has a low phase and a high phase. A first enable circuit enables first core data from the first core circuit in one of the low and high phases of the clock signal according to the phase select word.