Abstract: Co-simulation is a key technique in hardware／software co-design.A hardware／software cosimulation method is presented which integrates an event-driven VHDL hardware simulator with an instruction set simulator （ISS）.A bus function model described in C＋＋ language connects the two simulators.The implementation of ISS‚bus function model and co-simulation interface of the hardware simulator are discussed in detail.Synchronization of the hardware and software simulator is also illustrated. In the end‚a co-simulation example of an induction cooker control system is given to verify its effectiveness.