1 1 ONE-CHIP MICROCOMPUTER AND CONTROL METHOD THEREOF AS WELL AS AN IC CARD HAVING SUCH A ONE-CHIP MICROCOMPUTER

摘要

PURPOSE: A microcomputer is provided to execute built-in self test without using plural exclusive test terminals. CONSTITUTION: The one chip microcomputer(10) has a starting register(18) starting a test operation and a built-in self test starting pattern generator(19) setting initial values in test control circuits a pseudo random number generator(14), a logic circuit inspection compressor(15), a pattern generator(16) and a memory inspection compressor(17) for a built-in self test function. Built-in self test is started by the command of CPU(12) and the test results of a memory(11) and a logic circuit group(13) are read from the memory inspection compressor(17) and the logic circuit inspection compressor(15), it is compared with an expectation value which is previously stored in the memory(11) and the result is diagnosed in the one chip microcomputer(10).