Faces Calculator is a fully functional calculator panel compatible with the FACE_BOTTOM, which can be used for mathematical calculations or for customizing key functions. The panel adopts a 4*5 key layout design, covering basic function keys required for mathematical calculations. You can also remap them to custom function keys by modifying the firmware. The panel integrates a MEGA328 processor internally and works in slave mode via the I2C communication protocol (0x08).
