Patent attributes
A surgical instrument comprising a housing, a shaft assembly, a processor, and a memory is disclosed. The shaft assembly is replaceably connected to the housing. The shaft assembly comprises an end effector. The memory is configured to store program instructions which, when executed from the memory cause the processor to send an electrical interrogation signal to the attached shaft assembly, receive a response signal from the attached shaft assembly, cause a default function to be performed when a response signal is not received by the attached shaft assembly, determine an identifying characteristic of the attached shaft assembly as a result of the performance of the default function, and modify a control program based on the identifying characteristic of the attached shaft assembly.