BotronikS - Final code for all types of Arduino and PC users: -- HOME -- email: botronik@gmail.com
What you need to install or have installed before on your PC: see HERE

CPA4out: Status control of up to 4 Arduino outputs by TEXT commands (from PC, PLC...)

connections (click to enlarge)

CPA4out: Status control of up to 4 Arduino outputs by TEXT commands (from PC, PLC...)
Download the Free! HEX codes below, unpack, and upload to the proper Arduino board (Use a free net tool for example XLoader)
1. ATmega328-16MHz (MINI,NANO,UNO...): Hex-m328
2. AtMega2560 (Mega(ATMEGA2560)........): Hex-m2560
Based on the offered TEXT commands, you can develop your own PC, PLC ... communication code, and applications...

Available ASCII TEXT commands (Default: Baud=9600): Test uploaded code using some free serial software such as Termite.TextCommamd format: TextCommand + ENTER
AT - attention command (return OK) - example: AT
OxH - set OUTx (x=1-4) at Hi(5V) level - example: O1H
OxL - set OUTx (x=1-4) at Lo(0V) level - example: O12L
OA? - returns status of all outputs - example: OA?
OAH - set all outputs to Hi level - example: OAH
OAL - set all outputs to Lo level - example: OAL
 

Try and Test with Scada: soon