【AG32VH407】+驱动RGB灯带

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【AG32VH407】+驱动RGB灯带 [复制链接]

接上回，定时器呼吸灯，在中断中调整PWM的占空比来改变LED灯的亮度

这次采用DMA的方式来点亮RGB灯，灯珠采用WS2812

WS2812是单总线RGB灯，采用串联的方式可以方便的点亮多颗灯

   

 

24bit采用GRB888的方式通过IO将0码、1码组合后发送给灯珠

一般的有三种方式来实现时序波形的发送：

1、IO延时

2、SPI

3、定时器PWM

本次使用定时器PWM+DMA，参考GPTIMER例程

#define TIMEBASE 249
#define CODE1  170
#define CODE0  80

uint32_t gpt_pwmbuffer2[48*8*3+50]={};

void TestGpTimerPwmDma()
{
//初始化灯组缓存
  memset(gpt_pwmbuffer2, 0, 48*24+50);

	for (size_t i = 0; i < 8; i++)
{
  gpt_pwmbuffer[i] = CODE1;
  gpt_pwmbuffer2[i] = CODE1;
  gpt_pwmbuffer3[i][2] =  CODE1;
}
for (size_t i = 8; i < 8*2; i++)
{
  gpt_pwmbuffer[i] = CODE0;
  gpt_pwmbuffer2[i] = CODE0;
  gpt_pwmbuffer3[i][2] =  CODE0;
}
for (size_t i = 16; i < 8*3; i++)
{
  gpt_pwmbuffer[i] = CODE0;
  gpt_pwmbuffer2[i] = CODE0;
  gpt_pwmbuffer3[i][2] =  CODE0;
}


  // Use GPTIMER and DMA to generate arbitrary waveform
  SYS_EnableAHBClock(AHB_MASK_DMAC0);
  DMAC_Init();

    pwmdma_lli[0].Control = DMAC_MakeControl(DMAC_ADDR_INCR_ON, DMAC_ADDR_INCR_OFF, DMAC_WIDTH_32_BIT,
    DMAC_WIDTH_32_BIT, DMAC_BURST_1, DMAC_BURST_1, 0, DISABLE);
  for (uint32_t i = 0; i < (48*24+50); i++)
  {
  pwmdma_lli[i].SrcAddr = (uint32_t)&gpt_pwmbuffer2[i];
  pwmdma_lli[i].DstAddr = (uint32_t)&GPTIMER1->CCR0;
  pwmdma_lli[i].LLI     = (i<(48*24+50-1))?(uint32_t)&pwmdma_lli[i+1]:(uint32_t)&pwmdma_lli[0];
  pwmdma_lli[i].Control = pwmdma_lli[0].Control;
  }
  DMAC_ConfigLLI(DMAC_CHANNEL5, DMAC_MEM_TO_PERIPHERAL_PERIPHERAL_CTRL, 0, GPTIMER1_CC_DMA0_REQ, (uint32_t)pwmdma_lli);



  
  GPIO_AF_ENABLE(GPTIMER1_CH0);

  SYS_EnableAPBClock(APB_MASK_GPTIMER1);
  GPTIMER_InitTypeDef tm_init;
  GPTIMER_StructInit(&tm_init);
  tm_init.Autoreload = TIMEBASE;
  GPTIMER_Init(GPTIMER1, &tm_init);

  GPTIMER_OC_InitTypeDef oc_init;
  GPTIMER_OC_StructInit(&oc_init);
  oc_init.OCState = GPTIMER_OCSTATE_ENABLE;
  oc_init.OCMode = GPTIMER_OCMODE_PWM1;
  GPTIMER_OC_Init(GPTIMER1, GPTIMER_CHANNEL_CH0, &oc_init);

  GPTIMER_OC_EnableFast(GPTIMER1, GPTIMER_CHANNEL_CH0);
  GPTIMER_OC_EnablePreload(GPTIMER1, GPTIMER_CHANNEL_CH0);
  GPTIMER_EnableARRPreload(GPTIMER1);
  GPTIMER_EnableDmaUpdate(GPTIMER1);
  GPTIMER_EnableDmaCC0(GPTIMER1);
  GPTIMER_EnableAllOutputs(GPTIMER1);
  GPTIMER_EnableCounter(GPTIMER1);
  GPTIMER_GenerateEventUpdate(GPTIMER1); /* Enable UEV by setting UG bit to Load buffer data into preload registers */
  GPTIMER_GenerateEventUpdate(GPTIMER1); /* Enable UEV by setting UG bit to load data from preload to active registers */
 
}

更新LED数据缓存即可进行调光调色，尝试过使用单个dma.lli，但是地址貌似没有自增操作

IMG_3626

 

 

Jacktang

用WS2812的DMA的方式来点亮RGB灯，也挺顺溜的

 

lindawangj1

不错