# Help with modbus TCP/IP Client "Talking" to Codesys V3.5

**URL:** <https://community.factoryio.com/t/help-with-modbus-tcp-ip-client-talking-to-codesys-v3-5/655>\
**Category:** Support\
**Created:** [January 14, 2021, 6:13pm UTC](https://community.factoryio.com/t/help-with-modbus-tcp-ip-client-talking-to-codesys-v3-5/655 "2021-01-14T18:13:17Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![beatriz.santos](https://avatars.discourse-cdn.com/v4/letter/b/76d3ee/32.png) [@beatriz.santos](https://community.factoryio.com/u/beatriz.santos)\
**Post date:** [January 18, 2021, 10:55am UTC](https://community.factoryio.com/t/help-with-modbus-tcp-ip-client-talking-to-codesys-v3-5/655/3 "2021-01-18T10:55:35Z")

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Hi @thasamm,  
Are you using SP16 or higher? If so, CODESYS suffered some changes, so try this:

1. Check the “Discrete Bit Areas” box under ModbusTCP\_Slave\_Device \> General \> Configured Parameters and write the number of Coils and Discrete Inputs you need, as shown in the image below.

2. Map the variables (using Coils and Discrete Inputs).

3. Map these variables in FIO.

We’ll release a tutorial regarding these alterations. Meanwhile, let me know if this worked for you.

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_[View the full topic](https://community.factoryio.com/t/help-with-modbus-tcp-ip-client-talking-to-codesys-v3-5/655)._