This paper presents a brain activity monitoring system developed on a field programmable gate array (FPGA). A high definition multimedia interface (HDMI) core is introduced to display an anatomical brain on an LED/LCD monitor in realtime. A desired 2D view of a 3D anatomical image, selected beforehand by the user by a proposed user interface software, is converted to the jpeg formatted image. The registration of channels/voxels of interest in MNI or SCS coordinate systems is facilitated by the interface. To expedite the real-time dynamic displaying, RGB value of each pixel has been transformed to a single byte information and send it to the FPGA by a self-developed Ethernet core. The FPGA saves it in memory, displays the brain view on the screen. The FPGA is further notified with the pixel location of each registered channel. The FPGA becomes ready to update the color-map of the pixels of the registered channels to show the dynamic activity during a real-time experiment. The proposed system, validated by experimental dataset, has potential biomedical applications.