| 摘要 |
A system for determining a truth comprises a main unit which is employed together with an external memory, for example, ROM cartridge, floppy disk or the like. The main unit is operated following a program contained in the external memory. In the external memory and the main unit, the same semiconductor devices, for example, microprocessors are incorporated respectively, and the former device acts as a key device and the latter device acts as a lock device. The key device and the lock device are synchronized with each other, executing the same arithmetic operation following the same program. The results of this operation are exchanged with each other, and the two devices compare the result of operation by their own with the result of operation by the other, respectively. If the both coincide, software is determined to be true and the main unit is allowed to operate, but if not coincide, software is determined to be false and the main unit is left reset intact. Thereby, processing in the information processing apparatus is disabled when the software contained in the external memory is not true. |
