I made resin relay 3D printer based on RAMPS 1.4. RAMPS 1.4 board include Arduino Mega 2560 and RAMPS 1.4 stacking board. I have developed 3D printer with stepper motor using Arduino and C++ program. I can develop prototype using STM32, nRF52832, nRF52840, Arduino, ESP32, ESP8266 and PIC. l have deep technology and skill on BLE, WiFi, LoRa, motor control, PCB design and mass production.