Arduino open source single board computer boards arduino a000022 the arduino leonardo ethernet board is based on the atmega32u4 microcontroller and the new wiznet w5500 embedded ethernet controller the board has 20 digital io pins 7 can be used as pwm outputs and 12 as analog inputs additional features include a 16mhz xtal oscillator rj45 connection micro usb connector power jack icsp header and a reset button the leonardo eth differs from the preceding ethernet board in that the