Patent ID: 6185522
Filing Date: 2001-02-06
Classification: G06F

Abstract:
A method for emulating a target microcontroller that is configured to execute program code that is stored in an internal program memory only, the target microcontroller having a data IO port that is configured to provide a transfer of user data to and from the target microcontroller, the method comprising the steps of:providing an adapted microcontroller that is configured to execute the program code in lieu of the target microcontroller, the adapted microcontroller being substantially equivalent to the target microcontroller, including an IO port corresponding to the data IO port of the target microcontroller;providing the program code to the adapted microcontroller from an external source; andsynchronizing the adapted microcontroller according to a predefined machine cycle having a plurality of machine states;whereinthe adapted microcontroller is adapted to contain an internal multiplexer at the IO port that is configured tooutput a program address in a first machine state of the machine cycle for external evaluation of the program address,input program code corresponding to the program address during a subsequent machine state, andtransfer the user data during an other machine state,thereby allowing an emulation of the target microcontroller without requiring additional signal access pins on the adapted microcontroller.