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This is the help that opens from the question mark in the export window. The exported file is read from a microSD card, and the app ships an example to get started.
This is different from connecting the ESP32 over USB. Here the micro reads a file from a card and plays it on its own; there the app sends it the signal live and controls it. See Connect the device.

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General notes

1

Copy the file

The exported .txt goes to the root of the microSD card, under the same name you declare in the code.
2

Wire the reader

Over SPI. Set SD_CS to the pin you used for CS.
3

Declare one pin per channel

In the same order the file columns come out.
4

Set the step time

It comes from the metadata (STEP_TIME) if you exported it; otherwise you set it in the code.
5

Check the levels

The ESP32 outputs are 3.3 V. If your circuit runs at 5 V you need a level shifter.
6

For long signals, read in chunks

It is better to stream the card in batches than to load everything into RAM.

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The two examples

The help ships two code tabs, with a button to copy:
The digital file holds one row per change: the first column is the step and the rest are each channel value. Between rows the outputs stay as they are.The example reads row by row, writes the pins and waits until the step of the next row.

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Alternative: the complete firmware

If instead of writing the player you would rather use the one that already exists, the project ships a complete sketch that receives the signal over USB from the app and plays it, with control over start, stop, voltage, step time and RPM. See ESP32 firmware.