Patent ID: 6379252
Filing Date: 2002-04-30
Classification: A63F,G06F

Abstract:
A program rewrite system for rewriting data of a program, comprising:a rewrite machine; and a rewrite medium configured to be recycled by rewriting the contents thereof comprising, a semiconductor memory configured to rewritably store data of a program, a memory control part configured to control operation of said semiconductor memory and to change between a plurality of operation modes including a mode authorizing writing to said semiconductor memory and a mode inhibiting the same, and an operation circuit and a comparator; said operation circuit is configured to execute an operation with respect to data sent from said rewrite machine; said comparator is configured to perform a comparison between data of an operation result of said operation circuit and data sent from said rewrite machine; said plurality of operation modes are first to fourth operation modes (M1 to M4); said memory control part is configured to first enter said first operation mode when said rewrite medium is connected to said rewrite machine, to inhibit writing into said semiconductor memory in said first operation mode, and to change to said second operation mode when two data compared by said comparator do not coincide with each other, or to change to said third operation mode when the two data do coincide with each other; said memory control part is configured to stop its operation while inhibiting writing to said semiconductor memory in said second operation mode; said memory control part is configure to authorize writing to said semiconductor memory only with respect to writing from said memory control part in said third operation mode, to write prescribed data to said semiconductor memory, to read data and to change to said second operation mode when the read data do not coincide with each other, or to change to said fourth operation mode when the read data do coincide with each other; and said memory control part is configured to authorize writing from said rewrite machine to said semiconductor memory in said fourth operation mode.