We developed an 8 pixel electrochromic micro-display, which can be used as a data transmitter in a disposable bio-sensor chip for easy-to-use disease diagnosis system [1]. A fully-functionalized demonstration system consisting of the proposed electrochromic micro-display, a voltage booster, a control circuit, a Mg/AgCl on-chip battery and a temperature sensor instead of a bio-sensor was developed. The device was self-powered in NH4Cl solution and real-time data transmission using a pattern recognition system was demonstrated. The data transfer rate was 80 bps respectively.