| 摘要 |
PURPOSE:To prevent a converting means from being known from outside and the disable program contents to be read by forming a converting circuit internal address terminal positions and external address terminal positions on a semiconductor substrate. CONSTITUTION:A microprocessor circuit part 2 reads a program out of an external memory 10 according to addresses varied by an address converting circuit part 20 and operates a circuit part 3 to be controlled. The address converting circuit part 20 varies address bit positions of internal address terminal Ai1-AiN of the microprocessor circuit part 2 and address bit positions of external address terminals Ao1-AoN. Further, the address converting circuit part 20 is formed on the semiconductor substrate 1, so the address converting method can not be known from outside and the program contents are disabled to be read. |
