STM32_NeoPixel

A lightwieght, resource saving driver for WS2812 and WS2812B NeoPixel using STM32 HAL, Time PWM and DMA. Implemented on STM32F407 ( STM32F4DISCOVERY) using TIM8, channel 1 (PC6) and DMA.

Tutorial

STEP 1: THINGS YOU'LL NEED

• An STM32 Board. I'm using STM32F4DISCOVERY
• An LED strip of NeoPixel WS2812 or WS2812B
• And some jumper wires

Simply connect the 5V STM32F4DISCOVERY to 5V LED, GND connect to GND and DIN connect to PC6 pin.

STEP 2: LIBRARY

• In "Configure zone"
  • Change this "stm32f4xx_hal.h" to what your STM device.
  • "htim8" change this if you choice different timer.
  • "hdma_tim8_ch1" change this if you choice different timer or channel.
  • NUMBEROFLED is your maximum led of led strip.
  • LEDPERZONE is your led per zone (Only effect if you use rainbow mode)(Zone is number of led with same color).
• In "Configure if you know what to change" is default setting and some effect I already code.

STEP 3: USE LIBRARY

First, time to configure what type of LED you are using.

init_neopixel(WS2812);

Second, make all led is black.

all_black_render();

Some effect I imported to library.

One color in all led

void one_color_render(uint8_t blue,uint8_t red,uint8_t green);

Falling mode

void render_falling_mode(uint8_t blue,uint8_t red,uint8_t green,uint16_t delay);

Raising mode

void render_raising_mode(uint8_t blue,uint8_t red,uint8_t green,uint16_t delay);

Rainbow mode

void render_rainbow_cycle_mode(uint16_t delay);

I also add function to change HSV to RGB

static uint8_t *hsvtorbg(float H,float S,float V);

With H for Hue, S for Saturation, V for Value. And it will return a pointer which point to array HVS[3].

HSV[0] is GREEN.

HSV[1] is RED.

HSV[2] is BLUE.

STEP 4: CUSTOMIZE EFFECT

All data led must be store in here

color allrgb[BUFFERLED];

allrbg[BUFFERLED] is a struct have 3 variable of RGB for per led

typedef struct
{
  uint8_t red;
  uint8_t blue;
  uint8_t green;
}color;

After you save your data to array so you just use "render_neopixel" for display some effect you add.

void render_neopixel(void);

Reference

https://www.thevfdcollective.com/blog/stm32-and-sk6812-rgbw-led