Patent ID: 7231476

Claim:
A processor operable to perform a plurality of functions, said processor comprising: an input port; a storage element operable to receive and to store an input signal input via said input port, said input signal comprising at least one control value; control logic operable to control at least one of said functions of said processor in dependence on said at least one control value; and access logic operable to receive an access control signal and to disable access via said input port to said at least one control value stored in said storage element in dependence upon said access control signal, wherein said processor being operable in a plurality of modes and a plurality of domains said plurality of domains comprising a first domain and a second domain, and said processor further comprising; monitoring logic operable to perform a diagnostic function and capture diagnostic data from said processor; wherein said control value is indicative of whether said diagnostic function is available to capture diagnostic data from said first domain; and said control logic is operable to control availability of said diagnostic function in dependence on said at least one control value stored in said storage element.