Control an RGB led strip from a computer over the serial port (using an ardunio as the middle man).
- program the arduino with ws2801_control or ws2812_control
- Connect to the serial port using whatever library or tool you prefer (baud rate defaults to 115200)
- send 8 bit bytes, terminated by a byte with value 255 to signal the end of the command
- There's an example app written in ruby in ruby_test.rb for reference
| byte 0 | byte 1 | byte 2 | byte 3 | byte 5 |
|---|---|---|---|---|
| pixel number | red | blue | green | stop byte (always 255) |
for example, if you're using a terminal client that supports hex input:
| command | result |
|---|---|
| 00AA0000FF | pixel 0 is set to red brightness 170 |
| 16AAAAAAFF | pixel 22 is set to white brightness 170 |
| 2D000000FF | pixel 45 is set to black/off |
| led strip pin | arduino pin |
|---|---|
| DATA_PIN | 6 |
| led strip pin | arduino pin | notes |
|---|---|---|
| DATA_PIN | 11 | generally the blue wire |
| CLOCK_PIN | 13 | generally the green wire |
- Because 255 is a control character, you can't actually set a pixel to this brightness (but 253 looks almost identical)
- For ws2801, 254 is also a control character to update all the pixels, for ws2812, you can use 254 for pixel values
- when you first open the serial port on the ardunio, it reboots (it's a 'feature'). This means after you open the port, you need to wait a couple of seconds for it to boot, before you send any data, otherwise the data gets ignored.