Patent ID: 7853798
Filing Date: 2010-12-14
Classification: G06F,H04N

Abstract:
1. A program tamper detecting apparatus comprising: a random access memory (RAM), an external memory which stores a first code and a first program, wherein said first program is encrypted; an activation read only memory (ROM) which stores a second program which decrypts said first program; and a central processing unit (CPU) which is electrically connected to said external memory and said activation ROM, wherein said CPU decrypts said first program by executing said second program to obtain a decrypted first program, wherein said CPU detects tampering of said first program based on a comparison between said first code and a result of a predetermined operation executed on said second codes of said decrypted first program, wherein said CPU stores said decrypted first program in said RAM, reads out said second codes from said RAM, and detects tampering of said first program based on said comparison, wherein said external memory has an address data which specifies an address in said RAM, and wherein said CPU stores said decrypted first program in said RAM based on said address data, and reads out said second codes from said RAM based on said address data.