SEMICONDUCTOR INTEGRATED CIRCUIT FOR DATA PROCESSING

摘要

PURPOSE:To attain the secrecy of a program by sequentially generating the read address information of a program memory by means of a counting action and converting a counted initial value in the counting action into the holding value of a holding means which holds address information excluding an address '0' with the instruction of a reset state from outside. CONSTITUTION:When a reset signal R inputted from outside is asserted to be a high level, the counted initial value in the counting action of a program counter 3 is changed into the value which the holding means 4 previously holds. Then, the program counter 3 counts a program address from the changed initial value, and sequentially output the counted result as read address information of the program memory 2. The holding value is set in the holding means 4 in the manufacture process of an integrated circuit 1, and the holding value is decided so that it becomes equal to the starting address of the program in the program memory 2 excluding the address '0'.