A system comprises a plurality of components, scan chain selection logic coupled to the components, and override selection logic coupled to the scan chain selection logic. The first film is patterned by dry-etching using the resist pattern as a mask. The corrected measurement may be used to estimate intravascular blood volume andor fluid responsiveness of a patient. The keyboard also employs a novel one-hot-encoding circuitry that simplifies the wiring while allowing digital detection of any number of keys that are simultaneously depressed.