A system and method for incorporating design behavior and external stimulus in microdevice model feedback using a shared memory is presented. The invention describe herein uses the attached memory model to provide additional heuristics to an application executing on an emulation system's device model, which results in a more detail and real-life device emulation. The attached memory model provides a storage area for a runtime software environment to store emulation data, which is subsequently provided to the device model during emulation. The emulation data may include 1) randomization stimuli to the device model, 2) additional runtime data for checking heuristics, and 3) emulation data points that are otherwise not accessible to the device model.