Appendix

Here you can find all extra information you need for communicating with the master and slaves. In case your computer is the master, you can directly call functions and get a response from the slaves. In any other cases you have to control the master device through your machine.


Modbus Function Codes
Each command starts with an address followed by a function code. These are used to read data from discrete inputs and input registers. They can also read/write data on coils and holding registers of each Modbus device you address. On the next few pages you can find a brief description of all function codes.
Find the function code you are searching for

References
You can easily create modbus connections by using Ozeki's websites, but just in case you need detailed information. These datasheets can come in handy. For example if you are searching for a rare function or have difficulties understanding the Modbus TCP/IP package.
Download the most important Modbus references

FAQs
Industry analysts have reported over 7 million Modbus nodes in North America and Europe alone. See what most customers and industry leaders are interested in when considering Modbus technology. For example how to benefit from Modbus and what is Modbus TCP/IP protocol used for.
Search through the FAQs of the Modbus technology

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