A microcomputer chip is formed with a CPU core, a peripheral circuit, a built-in ROM, and a built-in RAM. An emulation functional chip is formed with an emulation control circuit for controlling the whole process of emulation. First electrode pads formed on the functional surface of the microcomputer chip are electrically interconnected to second electrode pads formed on the functional surface of the emulation functional chip with connecting bumps interposed therebetween. The microcomputer chip and the emulation functional chip are modularized using an insulating resin with the first electrode pads being connected to the second electrode pads. <IMAGE>