# Python LED Tutorial (NeoPixel Focus)

This tutorial is for the browser editor's ESP32-style mocks:

- `machine.Pin`
- `neopixel.NeoPixel`

Use `workspace/code/led_tutorial.py` while reading this guide.

## 1) Basic setup

```python
from machine import Pin
import neopixel

np = neopixel.NeoPixel(Pin(4), 12)
```

- `Pin(4)` means data pin 4 (matching common ESP32 examples).
- `12` is the number of LEDs in the strip/ring.
- `np` is your LED strip object.

## 2) Set one LED color

```python
np[0] = (255, 0, 0)  # red
np.write()
```

- Colors are `(red, green, blue)` from `0` to `255`.
- Nothing updates visually until `np.write()`.

## 3) Fill all LEDs

```python
np.fill((0, 0, 255))  # all blue
np.write()
```

## 4) Clear LEDs (turn off)

```python
np.fill((0, 0, 0))
np.write()
```

## 5) Animate over time

```python
import time

for step in range(20):
    np.fill((step * 10, 0, 255 - step * 10))
    np.write()
    time.sleep(0.08)
```

`time.sleep(...)` controls animation speed.

## 6) Moving pixel example

```python
for i in range(len(np)):
    np.fill((0, 0, 0))
    np[i] = (255, 120, 0)
    np.write()
    time.sleep(0.06)
```

## 7) Tips

- Keep color values in `0..255`.
- Use helper functions for repeated color logic.
- Start with short loops, then increase frames once behavior looks good.
- If the simulator is closed, run your script again to show updates.