In this article, we will take a look at the extended features of ‘Serial to Ethernet’ (S2E) gateway products from WIZnet. The target product is currently ‘WIZ550S2E’ and planning to be expanded to other products in the future.


The S2E gateway converts a Serial date to TCP/IP data and vice versa as shown below.

New Wireframe 1





One of the added features at this time is Modbus RTU/ASCII to Modbus TCP. We went one step further from the basic feature and applied the high-rank application protocol. The applied protocol is the Modbus mentioned above.

New Wireframe 1 copy





To briefly describe the Modbus, Modbus was created in 1979 as a serial communication protocol for programmable logic controllers(PLCs) from Modicon(Currently calls Schneider Electric) and is based on Master/Slave communication.

In other words, the slave responds if the master requests. Initially, only serial-based RTU and ASCII existed, but now Ethernet-based TCP is also supported.

Now it has become one of the main industrial protocols for the following reasons.

  • Developed with industrial applications in mind.
  • Open source and free
  • Easy to distribute and maintain
  • Easy to manipulate the information in a bit or word unit without limitation of the vendors

The extended Modbus RTU/ASCII to Modbus TCP function is available as shown below.


New Wireframe 1 copy 2


















You can apply the WIZnet S2E gateway in the middle to convert the data if the Slave Device that you own only supports serial and the running Master Device only supports ethernet.


Curator : ricky from WIZnet
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