Contents 1 INTRODUCTION 2 TECHNICAL SPECIFICATIONS 3 CHANGES COMPARED TO THE PREVIOUS VERSION (V4) 4 ELECTRONIC SCHEMATIC 5 PCB BOARD DESIGN - Order now at JLCPCB 6 LIST OF ELECTRONIC COMPONENTS 7 STEPS TO UPLOAD A PROGRAM 8 EXTERNAL PARTS AND CONNECTIONS 9 LIST OF EXTERNAL TERMINALS AND ATMEGA328P-AU 10 TEST CODES 10.1 OUTPUTS 10.2 INPUTS AND OUTPUTS 10.3 ANALOG INPUTS 10.4 SERIAL PLOTER 10.5 REAL TIME CLOCK (RTC) INTRODUCTION At the beginning of this year 2020 a video of the PLC V4 was published. whose device still had to be improved, therefore, for this version 4.1, a Real Time Clock and a DC DC step down source have been integrated. PLC with arduino (ATmega328p AU) V4.1, is a programmable logic controller that was designed by Electroall, whose circuit is based on the SIEMENS S7 1200 CPU1214c PLC device with relay outputs. Initially, the current version will have a 24VDC power supply like all industrial devices. In addition, it includes a Real Time Clock (RTC). S