Patent ID: 6584540
Filing Date: 2003-06-24
Classification: G11C

Abstract:
A flash memory rewriting circuit being integrated into a microcontroller having a CPU, a flash memory in which an operating program defining an operation of said CPU is stored and an input/output section to input and output data to and from external devices in order to rewrite, by operations of said CPU, said operating program stored in said flash memory, comprising:a transfer program storing region provided, within said flash memory, in a memory region other than an operating program storing region in which said operating program is stored, which stores a data transfer program to transfer a data for rewriting said operating program to said flash memory through said external devices when said data transfer program is read and executed by said CPU; and a read only memory storing a rewriting execution program to have rewriting data fed by external devices written on said operating program storing region of said flash memory when said rewriting execution program is read and executed by said CPU.