A system on chip processor, that is, a semiconductor integrated circuit in which a processor, a cache memory and the like are integrated into one chip, includes a test controller, and a trace memory. The test controller generates test control signals in response to test flag signals generated from a processor. The trace memory stores a transmission data signal between the processor and a cache memory, a device under test, in response to the test control signals. Since the trace memory is provided within the integrated circuit, an operation of the device under test, which is configured in the integrated circuit, can be tested without disassembling the integrated circuit even after the integrated circuit is completely manufactured.