METHOD AND APPARATUS FOR PROVIDING OPTIMIZED ACCESS TO CIRCUITS FOR DEBUG, PROGRAMMING, AND TEST

An access interface for accessing electrical nodes of an electronic circuit for programming, testing, and debugging the electronic circuit. The access interface includes a protocol generator and a data generator that may be programmed to apply control and/or data sequences directly to the electronic circuit. The access interface performs operational commands based upon a plurality of states included in a programmable state machine. By suitably programming the protocol generator, the data generator, and the state machine, electrical nodes of the electronic circuit can be accessed in reduced time using a reduced number of operations. The access interface is controlled by a test resource apparatus, which communicates with the electronic circuit connected to the access interface. The access interface may be implemented as a downloadable circuit, e.g., it may be programmed into a programmable logic device by the test resource apparatus. Alternatively, the access interface may be implemented as a fixed/permanent circuit in an ASIC.