1. A method for configuring an electronic device comprising: forming first configuration data for the device, the first configuration data including data for forming a first module for generating a volatile response that depends on fabrication variation among like devices configured according to the configuration data; configuring the device using the first configuration data and using the configured device to generate a first volatile response from the first module and outputting a signal from the device that depends on the volatile response; and forming second configuration data for the device based on the outputted signal, the second configuration data including data for forming the first module and data for implementing a comparison of the first volatile response and a volatile response generated by the first module according to the second configuration data.