| 摘要 |
PURPOSE:To prevent software from being used by stealth, by opening a bus between a CPU and memory by means of a HALT command and placing the internal memory under the control of a CPU in a software scrambler. CONSTITUTION:A computer and software scrambler are connected with each other through an external address bus 5 and external data bus 6 and a HALT command is given to the computer from the scrambler through a control line 7. When such constitution is used, the buses 5 and 6 between a memory 2 and CPU1 are opened inside the computer and the memory 2 is placed under the control of a CPU3 in the scrambler. Under this condition, a program 9 is started and a prescribed scramble is given to software on the memory 2, and then, the scrambled result is stored in an area 10. By opening the buses 5 and 6 by means of the HALT command and placing the memory 2 under the control of the CPU3 in this way, a prescribed scramble can be given to software on the memory 2 and software can be prevented from being used by stealth. |
