Abstract: A microprocessor for performing an interrupt operation receives an interrupt-enable signal representative of occurrence of at least interrupt request and interrupt level information representative of a selected one of interrupt sources issuing the interrupt request and includes an interrupt receiving unit activated by the interrupt-enable signal for producing vector fetching command information when an interrupt operation responsive to the interrupt level information is acceptable, an interrupt vector generation unit activated by the interrupt-enable signal for generating interrupt vector information, and an execution unit fetching the interrupt vector information in response to the vector fetching command information, the execution unit thereby initiates an interrupt operation by use of the interrupt vector information and returning interrupt acknowledge information as a part of the interrupt operation.

Abstract: In measuring the ac specifications of a microprocessor having within one chip, a clock generator which generates a clock signal, a first connecting terminal for connecting a crystal oscillator which regulates the oscillation frequency of the clock generator, a first driver which amplifies the power of the clock signal, a second connecting terminal which receives an output of the first driver, a peripheral circuit which receives the supply of a clock signal, a CPU which is operated by the clock signal and controls the operation of the peripheral circuit, a second driver which amplifies the power of an output of the CPU, and a third connecting terminal which receives the supply of an output of the second driver, there are executed a first step of measuring the ac specification of the clock generator with the output to the second connecting terminal by applying test pulses from an IC tester to the first connecting terminal under the condition in which the crystal oscillator is removed, and a second step of measu