Patent ID: 7051231

Claim:
A microprocessor system for correcting a faulty program code segment in a program ROM of an embedded microprocessor system, the microprocessor system having a program counter, the program counter comprising binary bits for storing the address of the next program code segment to be executed, the program correcting apparatus comprising: a program RAM for storing a program code segment that is executed in place of the faulty program code segment stored in the program ROM; an address RAM for storing a plurality of correction entries, one correction entry being accessed and output according to a least significant bits portion of a value in the program counter; an address detection unit connected to the program counter and the output of the address RAM, the address detection unit being capable of determining if a program code segment at an address in the program RAM specified by the correction entry outputted from the address RAM is to be executed; wherein when the address detection unit determines that a program code segment at an address in the program RAM is to be executed, the address in the program counter is changed to access the program code segment in the program RAM.