Create a TCP connection between PLC Siemens S7-1200 and Arduino Uno or Mega

[alexandra]

This how-to is meant to teach you how to establish a raw tcp connection between Arduino Uno/Mega and PLC Siemens S7-1200.

1. Prerequisites:

   • Siemens PLC S7-1200
   • Arduino Uno/Mega
   • Ethernet shield or native Wi-Fi
   • Siemens Switch for LAN connections
   • TIA Portal
   • Arduino IDE
   • Ethernet library for Arduino (based on the shield used)

2. Hardware Network Setup

   • PLC ethernet port > Switch
   • Ethernet shield > Switch
   • LAN cable from laptop > Switch for TIA portal
   • Set static IPs: 192.168.0.1 (for PLC, Device Configuration > PROFINET Interface) and 192.168.0.xx (for Arduino)

3. Configuration in TIA Portal
   3.1. Add TCON and TSEND/TRCV instructions in Main_OB1

   • TCON - establish connection
     • Local Device: Active
     • Remote IP: 192.168.0.xx (Arduino’s IP address)
     • Remote Port: match Arduino server port
     • Active connection: TRUE
     • Type: TCP
   • TSEND - send data
   • TRCV - receive data
     3.2. Connections in Main_OB1 for TCON:
   • REQ - bool
   • CONNECT - “DB_TCP”.CONNECT (data block created specifically for TCP connection)
   • DONE - bool
   • BUSY - bool
   • ERROR - bool
   • STATUS - word
     
     

   3.3. Connections in Main_OB1 for TSEND/TRCV:

   • REQ - bool
   • ID - 1
   • DATA - “DB_TCP”.SEND_CODE/RCV_CODE
   • In SEND_CODE/RCV_CODE you set the type of data you want to send over (in this case of use, SEND_CODE is a char)
     
     
     
     
     
     
     
     

4. Example of sending over the data in Main_OB1

   • Created a function block to handle all the char commands that are being sent
     
     
   • Example of the function block