# `led_strip_spi` example
## What the example does
The example runs the following effects in a loop.
- changes the colours of all the LEDs using [_color wheel_](https://duckduckgo.com/?q=color+wheel).
- simply rotates the colours (B -> G -> R)
- displays rainbow colors on the strip, scrolling the rainbow
## Configuration
You can change the number of pixels in a strip by `idf.py menuconfig` or `make
menuconfig`. See `CONFIG_EXAMPLE_N_PIXEL` under `Example configuration`. The
default is 8 pixels.
## Hookup
| Pin on `SK9822` | Destination |
|-----------------|------------------------------|
| `5V` | `5V` |
| `CI` | `GPIO14` (ESP32 and ESP8266) or `GPIO6` (ESP32C3) |
| `DI` | `GPIO13` (ESP32 and ESP8266) or `GPIO7` (ESP32C3) |
| `GND` | `GND` |
`SK9822` LED strip has `CI` and `DI` at both end of the strip. Make sure the
direction of data flow is correct. The `GPIO`s must be connected to the first
LED. My strip has arrows on the strip like below.
```text
--------------------- Data flow ------------------>
.--------------------------.
| |
| .-------. .-------. |
GND ----- GND -+--| --> G |----| --> G |--+- GND
GPIO14 ----- CI -+--| |----| |--+- CI
GPIO13 ----- DI -+--| LED |----| LED |--+- DI
5V/Vin ----- 5V -+--| |----| |--+- 5V
| `-------' `-------' |
| the first LED |
`--------------------------'
```
## Notes
Start with a small number of LED pixels. Make sure the 5 V power source is
stiff enough. A `SK9822` draws up to 60 mA. A cheap `ESP32` development board
with `AMS1117` can source 8 `WS2812` pixels from USB 5V `VIN` _with_ the
default example code.
Make data lines short. The clock speed is an order of `Mhz`.
`SK9822` is 5V device but you _might_ be able to drive it from ESP32, which is
3.3V device, without level shifter. See also [README.md for led_strip](../led_strip/README.md).
To create a project from this example, run:
idf.py create-project-from-example "esp-idf-lib/led_strip_spi=1.0.5:default"