The biomicrorobotic is an emerging technology involving microelectronic, robotic and biomedical sciences and technologies in order to help medicine to perform better treatments. Autonomous biomicrorobots (BMR) needs a control core to perform special tasks. This paper describes a microcontroller architecture selected to perform BMR's control algorithms for legs displacement. This microcontroller is based on an 8-bits RISC architecture and coupled with a Manchester decoder for communication purpose. As input signal goes through a serial port, a serial/parallel converter has been implemented to load instructions in the microcontroller. The technology CMOS 0.18 /spl mu/m is targeted for implementation. The output signals for legs control will be transmitted through a 8-bits parallel ports.