cmake_cpputest_template/inc/extralibs/ws2812b_simple.h
2025-12-23 14:33:54 -08:00

83 lines
1.8 KiB
C

/* Single-File-Header for using asynchronous LEDs with the CH32V003 using GPIO.
Copyright 2023 <>< Charles Lohr, under the MIT-x11 or NewBSD License, you choose!
If you are including this in main, simply
#define WS2812BSIMPLE_IMPLEMENTATION
You may also want to define
#define WS2812BSIMPLE_NO_IRQ_TWEAKING
*/
#ifndef _WS2812B_SIMPLE
#define _WS2812B_SIMPLE
#include <stdint.h>
void WS2812BSimpleSend( GPIO_TypeDef * port, int pin, uint8_t * data, int len_in_bytes );
#ifdef WS2812BSIMPLE_IMPLEMENTATION
#include "funconfig.h"
#if FUNCONF_SYSTICK_USE_HCLK != 1
#error WS2812B Driver Requires FUNCONF_SYSTICK_USE_HCLK
#endif
void WS2812BSimpleSend( GPIO_TypeDef * port, int pin, uint8_t * data, int len_in_bytes )
{
int port_id = (((intptr_t)port-(intptr_t)GPIOA)>>10);
RCC->APB2PCENR |= (RCC_APB2Periph_GPIOA<<port_id); // Make sure port is enabled.
int poffset = (pin*4);
port->CFGLR = ( port->CFGLR & (~(0xf<<poffset))) | ((GPIO_Speed_2MHz | GPIO_CNF_OUT_PP)<<(poffset));
int maskon = 1<<pin;
int maskoff = 1<<(16+pin);
port->BSHR = maskoff;
uint8_t * end = data + len_in_bytes;
while( data != end )
{
uint8_t byte = *data;
int i;
for( i = 0; i < 8; i++ )
{
if( byte & 0x80 )
{
// WS2812B's need AT LEAST 625ns for a logical "1"
port->BSHR = maskon;
DelaySysTick(25);
port->BSHR = maskoff;
DelaySysTick(1);
}
else
{
// WS2812B's need BETWEEN 62.5 to about 500 ns for a logical "0"
#ifndef WS2812BSIMPLE_NO_IRQ_TWEAKING
__disable_irq();
#endif
port->BSHR = maskon;
asm volatile( "nop\nnop\nnop\nnop" );
port->BSHR = maskoff;
#ifndef WS2812BSIMPLE_NO_IRQ_TWEAKING
__enable_irq();
#endif
DelaySysTick(15);
}
byte <<= 1;
}
data++;
}
port->BSHR = maskoff;
}
#endif
#endif