WS2812 datasheet(68/98 Pages) RASPBERRY-PI

68 / 98 page

Now the first pixel is at the top right. Pixels increment top-to-bottom — it’s now column major. The order of the

columns is still progressive though.

We declare the matrix thusly:

Adafruit_NeoMatrix matrix = Adafruit_NeoMatrix(5, 8, 6,

NEO_MATRIX_TOP

+ NEO_MATRIX_RIGHT +

NEO_MATRIX_COLUMNS + NEO_MATRIX_PROGRESSIVE,

NEO_GRB

+ NEO_KHZ800);

The first two arguments — 5 and 8 — are the width and height of the matrix, in pixels. The third argument — 6 — is the

pin number to which the NeoPixels are connected. On the shield this is hard-wired to digital pin 6, but standalone

matrices are free to use other pins.

The next argument is the interesting one. This indicates where the first pixel in the matrix is positioned and the

arrangement of rows or columns. The first pixel must be at one of the four corners;

which corner is indicated by adding

either NEO_MATRIX_TOP or NEO_MATRIX_BOTTOM to either NEO_MATRIX_LEFT or NEO_MATRIX_RIGHT. The

row/column arrangement is indicated by further adding either NEO_MATRIX_COLUMNS or NEO_MATRIX_ROWS to

either NEO_MATRIX_PROGRESSIVE or NEO_MATRIX_ZIGZAG. These values are all added to form a single value as in

the above code.

NEO_MATRIX_TOP + NEO_MATRIX_RIGHT + NEO_MATRIX_COLUMNS + NEO_MATRIX_PROGRESSIVE

https://learn.adafruit.com/adafruit-neopixel-uberguide

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WS2812 Datasheet(PDF) 68 Page - Raspberry Pi Holdings PLC