architecture of programming of a circuit with a memoire, rome et memoire, flash

摘要

An architecture for an integrated circuit with in-circuit programming includes a microcontroller on an integrated circuit and one or more banks of non-volatile memory which store instructions, including an in-circuit programming (ICP) set of instructions. Using a control program stored on the device, the device interactively establishes an in-circuit programming exchange with a device external to the integrated circuit and uses data obtained in the exchange to update software for the microcontroller. Portions of the ICP code which are likely to change between different application environments are stored in reprogrammable flash memory cells. Other portions of the ICP code, which are not likely to change between different application environments, are stored in space-efficient mask ROM memory cells. In this way, the ICP system can be flexibly adapted to different application environments, while conserving on silicon area occupied the ICP system.