An optical interface incorporated into a multi-channel telemetry device used principally to provide data representing physiological conditions in a human subject. Information is transmitted without the need of a bio-compatible electrical connection via an optical link which conveys calibration parameters and commands to control the operation of the telemeter. The optical link is configured to reside completely on an integrated circuit chip. Of the three channels designed into the chip by means of appropriate electronic circuitry, one of the channels measures temperature and the other two channels are dedicated to develop generic information selectively derived from other physiological conditions. Calibration information that is programmed into the telemeter by means of the optical interface is retrieved by time division multiplexing with one of the generic channels.