DCC Light Decoder U2.2

Purpose
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Project UNION based ESP32 DCC/MQTT light decoder supporting programmable LED outputs.

Important
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This documentation was produced from the supplied project package.
No source code has been modified.

Developer checklist
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- Install the ESP32 board package.
- Install the required Project UNION libraries used by the project.
- Open the .ino file from its own sketch folder.
- Compile without changing source files.
- Verify all GPIO assignments against the supplied hardware diagram.
- Test on one decoder before programming additional units.

Notes
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During documentation generation no source code has been modified.
If inconsistencies are found between the code and the diagrams they will be
reported instead of corrected automatically.