text: Various drug pumps are known for pumping fluid to a patient in connection with treatment of various medical conditions. Drug pumps are known which include a reusable control module with a disposable or reusable fluid reservoir cassette wherein the reservoir is either self-contained with the cassette or remote from the cassette. The control module pumps fluid from the cassette to the patient when the cassette is attached or mounted to the control module.
  There is a need for using the control module in connection with different fluid reservoir cassettes. The cassettes may differ in the nature of the drugs or other fluid contained therein. Other differences might relate to the manner in which the fluid reservoir component cooperates with the control module to deliver the fluid to the patient. For example, the control module may include a pumping mechanism which engages a tube extending from the fluid reservoir cassette. The fluid reservoir cassettes may have variations in tubing size. In that case, it is important to identify to the control module the size of the tubing attached to the fluid reservoir cassette so that the proper amount of drug is delivered to the patient.
  There is also a need for identifying a proper cassette from an improper cassette mounted to the control module. In some cases, the control module may be programmed or configured to pump fluid in a certain therapy from a particular cassette. If an improper cassette is mounted to the control module, there is a danger the patient may be given an improper drug.
  There has arisen a need for systems and methods for identifying a fluid reservoir cassette which mounts to a control module of a drug pump.