Abstract: In a program-invocation-count measuring system, first and second identification codes are acquired and exchanged among processes as a broadcast or response signal. The first identification code is used for determining whether there are currently active processes which have been activated by invoking the same program. On the other hand, the second identification code is used for determining whether a response signal received by a process is the same as a broadcast signal transmitted earlier by the process.

Abstract: An emulator apparatus includes an access information memory in which, when an emulation program makes a write access to a memory address of a microcomputer, and information showing the presence of the write access is related to the write-accessed address and is stored. A break circuit to break execution of the emulation program when the emulation program makes a read access to the memory address of the microcomputer is provided, and the access information memory does not contain information showing the presence of the write access to the read-accessed address.