# Create CSV parse presets

This guide shows how to create a `presets.json` file so that ModbusScope automatically applies the right parse settings when opening certain CSV files.

## Steps

1. Create a file named `presets.json` and place it in one of these locations:
   - `C:\Users\<USER>\Documents\ModbusScope\presets.json` (Windows, checked first)
   - Same folder as the ModbusScope executable (fallback)

2. Write your presets using this structure:

   ```json
   {
     "presets": [
       {
         "name": "My preset",
         "keyword": "-mydevice",
         "fieldseparator": ";",
         "decimalseparator": ",",
         "thousandseparator": " ",
         "commentsequence": "//",
         "column": 1,
         "labelrow": 1,
         "datarow": 2
       }
     ]
   }
   ```

3. Adjust the values to match your file format. See [Reference: Preset file format](../reference/preset-file-format.md) for all available fields.

4. Save the file and reopen ModbusScope (or open a CSV file — presets are loaded when the import dialog opens).

**Result:** When you open a CSV file whose name contains the keyword (e.g. a file named `log-mydevice.csv`), the matching preset is selected automatically. If no keyword matches, you can pick a preset from the dropdown in the import dialog.

## Notes

- If a valid preset file is found, it replaces the built-in presets entirely.
- A preset can omit `keyword` if you always want to select it manually.
- Timestamps in seconds: set `"timeinmilliseconds": false` to have ModbusScope convert them on load.
- Existing `presets.xml` files continue to work without changes. See [Reference: Preset file format — backward compatibility](../reference/preset-file-format.md#backward-compatibility-xml-format).

## See also

- [Reference: Preset file format](../reference/preset-file-format.md)
- [Open a CSV data file](open-csv-file.md)