LED Blink by Remote PC Using WIZwiki-W7500 Mbed Platform

I introduce a LED blink controlling from remote PC through network (TCP protocol).

A TCP client program runs in the PC and a TCP server runs in a WIZwiki-W7500 mbed platform board. W7500 transmits data to PC and receives data from PC through TOE(TCP/IP Offload Engine). W7500 controls LED by executing some command received from remote PC.

Using mbed library, the software can be easily implemented.

You can learn how to control LED from remote PC.

This example will help makers who want to make IoT device for Home Automation or Building Automation.

Step 1: Tools and Materials

• WIZwiki-W7500 board
• USB cable
• LAN cable
• Ethernet Hub (or Switch): It should have DHCP function.

Step 2: Hardware

Network configuration diagram

Step 3: ​Software

• Compiler
  
  • ARM mbed Web Compiler
• Test program
  
  • Terminal program
    
    • EX) Teraterm, Hercules, Hyperterminal, etc.
    • It is used for checking serial port message.
  • TCP/IP Client Server terminal program
    
    • EX) Hercules etc.
    • It is used for transmitting and receiving message.
• Example code
  
  • TCP_LED_Control-WIZwiki-W7500

Step 4: Firmware Programming and Connecting Boards

1. FW programming
   
   • Compile the example code in the mbed developer’s site.
   • Download compiled binary file into the WIZwiki board.
2. Connecting boards
   
   • Connect your PC and a Hub with LAN cable.
   • Connect a WIZwiki-W7500 board and a Hub with LAN cable.
   • Connect the PC and the WIZwiki-W7500 board with USB cable.

Step 5: Run Test Software and Check Serial Port Message

1. Run test software
   
   • Execute Serial Terminal program in the PC.
   • First press Reset Switch of WIZwiki board and check the message. IP address was assigned after DHCP operation.
   • Execute Hercules program on a PC.
2. Check serial port message
   
   • Set TCP Client menu in the Hercules program.
   • This is a screenshot of Teraterm. The Client of PC is connected to Server of WIZwiki-W7500.
   • TCP Client send some message to WIZwiki board. The WIZwiki board sends back reversed message to TCP Client.

Step 6: Send LED Control Message

1. Send LED control message and Check LED blink
   • TCP Client sends “LED_ON” to WIZwiki, then LED turns on.
   • TCP Client sends “any message” except “LED_ON” to WIZwiki, the LED turns off.
   • LED ON/OFF can be shown in blue circle part of the board picture.

Step 7: Test Result

Check LED blink

• LED ON/OFF can be shown in blue circle part of the board picture.

This is the last page of this tutorial.

LED ON and OFF can be controlled from remote PC through network (TCP protocol).

Using ARM mbed library and example codes, the software can be easily implemented.

• ARM mbed
• WIZnet team page in mbed

This example will help you make your own IoT device that needs Ethernet connection for Home Automation or Building Automation.