STM32底层LL库DAC输出LL篇14

Posted:   2020-08-22

Status:   Completed

Tags :   STM32 CUBE LL DAC

Categories :   STM32 CUBE LL DAC

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配置DAC

  • 和HAL库配置一样
  • 在高级设置里为DAC选择LL库,TIM2选择LL库
  • 生成代码

DAC函数

DAC结构体分析

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/**
  * @brief  Structure definition of some features of DAC instance.
  */
typedef struct
{
  uint32_t TriggerSource;               /*!< Set the conversion trigger source for the selected DAC channel: internal (SW start) or from external peripheral (timer event, external interrupt line).
                                             This parameter can be a value of @ref DAC_LL_EC_TRIGGER_SOURCE

                                             This feature can be modified afterwards using unitary function @ref LL_DAC_SetTriggerSource(). */

  uint32_t WaveAutoGeneration;          /*!< Set the waveform automatic generation mode for the selected DAC channel.
                                             This parameter can be a value of @ref DAC_LL_EC_WAVE_AUTO_GENERATION_MODE

                                             This feature can be modified afterwards using unitary function @ref LL_DAC_SetWaveAutoGeneration(). */

  uint32_t WaveAutoGenerationConfig;    /*!< Set the waveform automatic generation mode for the selected DAC channel.
                                             If waveform automatic generation mode is set to noise, this parameter can be a value of @ref DAC_LL_EC_WAVE_NOISE_LFSR_UNMASK_BITS
                                             If waveform automatic generation mode is set to triangle, this parameter can be a value of @ref DAC_LL_EC_WAVE_TRIANGLE_AMPLITUDE
                                             @note If waveform automatic generation mode is disabled, this parameter is discarded.

                                             This feature can be modified afterwards using unitary function @ref LL_DAC_SetWaveNoiseLFSR(), @ref LL_DAC_SetWaveTriangleAmplitude()
                                             depending on the wave automatic generation selected. */

  uint32_t OutputBuffer;                /*!< Set the output buffer for the selected DAC channel.
                                             This parameter can be a value of @ref DAC_LL_EC_OUTPUT_BUFFER

                                             This feature can be modified afterwards using unitary function @ref LL_DAC_SetOutputBuffer(). */

} LL_DAC_InitTypeDef;
  • DAC触发源TriggerSource
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/** @defgroup DAC_LL_EC_TRIGGER_SOURCE DAC trigger source
  * @{
  */
#define LL_DAC_TRIG_SOFTWARE               (DAC_CR_TSEL1_2 | DAC_CR_TSEL1_1 | DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger internal (SW start) */
#define LL_DAC_TRIG_EXT_TIM3_TRGO          (                                  DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger from external peripheral: TIM3 TRGO. */
#define LL_DAC_TRIG_EXT_TIM15_TRGO         (                 DAC_CR_TSEL1_1 | DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger from external peripheral: TIM15 TRGO. */
#define LL_DAC_TRIG_EXT_TIM2_TRGO          (DAC_CR_TSEL1_2                                  ) /*!< DAC channel conversion trigger from external peripheral: TIM2 TRGO. */
#define LL_DAC_TRIG_EXT_TIM8_TRGO          (                                  DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger from external peripheral: TIM8 TRGO. */
#define LL_DAC_TRIG_EXT_TIM4_TRGO          (DAC_CR_TSEL1_2                  | DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger from external peripheral: TIM4 TRGO. */
#define LL_DAC_TRIG_EXT_TIM6_TRGO          0x00000000U                                        /*!< DAC channel conversion trigger from external peripheral: TIM6 TRGO. */
#define LL_DAC_TRIG_EXT_TIM7_TRGO          (                 DAC_CR_TSEL1_1                 ) /*!< DAC channel conversion trigger from external peripheral: TIM7 TRGO. */
#define LL_DAC_TRIG_EXT_TIM5_TRGO          (                 DAC_CR_TSEL1_1 | DAC_CR_TSEL1_0) /*!< DAC channel conversion trigger from external peripheral: TIM5 TRGO. */
#define LL_DAC_TRIG_EXT_EXTI_LINE9         (DAC_CR_TSEL1_2 | DAC_CR_TSEL1_1                 ) /*!< DAC channel conversion trigger from external peripheral: external interrupt line 9. */
  • 是否自动输出噪声或三角波WaveAutoGeneration
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/** @defgroup DAC_LL_EC_WAVE_AUTO_GENERATION_MODE DAC waveform automatic generation mode
  * @{
  */
#define LL_DAC_WAVE_AUTO_GENERATION_NONE     0x00000000U                     /*!< DAC channel wave auto generation mode disabled. */
#define LL_DAC_WAVE_AUTO_GENERATION_NOISE    (               DAC_CR_WAVE1_0) /*!< DAC channel wave auto generation mode enabled, set generated noise waveform. */
#define LL_DAC_WAVE_AUTO_GENERATION_TRIANGLE (DAC_CR_WAVE1_1               ) /*!< DAC channel wave auto generation mode enabled, set generated triangle waveform. */
  • 选择噪声生成器的低通滤波或三角波的幅值WaveAutoGenerationConfig
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/** @defgroup DAC_LL_EC_WAVE_NOISE_LFSR_UNMASK_BITS DAC wave generation - Noise LFSR unmask bits
  * @{
  */
#define LL_DAC_NOISE_LFSR_UNMASK_BIT0      0x00000000U                                                         /*!< Noise wave generation, unmask LFSR bit0, for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS1_0   (                                                   DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[1:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS2_0   (                                  DAC_CR_MAMP1_1                 ) /*!< Noise wave generation, unmask LFSR bits[2:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS3_0   (                                  DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[3:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS4_0   (                 DAC_CR_MAMP1_2                                  ) /*!< Noise wave generation, unmask LFSR bits[4:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS5_0   (                 DAC_CR_MAMP1_2                  | DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[5:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS6_0   (                 DAC_CR_MAMP1_2 | DAC_CR_MAMP1_1                 ) /*!< Noise wave generation, unmask LFSR bits[6:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS7_0   (                 DAC_CR_MAMP1_2 | DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[7:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS8_0   (DAC_CR_MAMP1_3                                                   ) /*!< Noise wave generation, unmask LFSR bits[8:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS9_0   (DAC_CR_MAMP1_3                                   | DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[9:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS10_0  (DAC_CR_MAMP1_3                  | DAC_CR_MAMP1_1                 ) /*!< Noise wave generation, unmask LFSR bits[10:0], for the selected DAC channel */
#define LL_DAC_NOISE_LFSR_UNMASK_BITS11_0  (DAC_CR_MAMP1_3                  | DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Noise wave generation, unmask LFSR bits[11:0], for the selected DAC channel */
/**
  * @}
  */

/** @defgroup DAC_LL_EC_WAVE_TRIANGLE_AMPLITUDE DAC wave generation - Triangle amplitude
  * @{
  */
#define LL_DAC_TRIANGLE_AMPLITUDE_1        0x00000000U                                                         /*!< Triangle wave generation, amplitude of 1 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_3        (                                                   DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 3 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_7        (                                  DAC_CR_MAMP1_1                 ) /*!< Triangle wave generation, amplitude of 7 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_15       (                                  DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 15 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_31       (                 DAC_CR_MAMP1_2                                  ) /*!< Triangle wave generation, amplitude of 31 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_63       (                 DAC_CR_MAMP1_2                  | DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 63 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_127      (                 DAC_CR_MAMP1_2 | DAC_CR_MAMP1_1                 ) /*!< Triangle wave generation, amplitude of 127 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_255      (                 DAC_CR_MAMP1_2 | DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 255 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_511      (DAC_CR_MAMP1_3                                                   ) /*!< Triangle wave generation, amplitude of 512 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_1023     (DAC_CR_MAMP1_3                                   | DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 1023 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_2047     (DAC_CR_MAMP1_3                  | DAC_CR_MAMP1_1                 ) /*!< Triangle wave generation, amplitude of 2047 LSB of DAC output range, for the selected DAC channel */
#define LL_DAC_TRIANGLE_AMPLITUDE_4095     (DAC_CR_MAMP1_3                  | DAC_CR_MAMP1_1 | DAC_CR_MAMP1_0) /*!< Triangle wave generation, amplitude of 4095 LSB of DAC output range, for the selected DAC channel */
  • DAC输出缓存OutputBuffer
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/** @defgroup DAC_LL_EC_OUTPUT_BUFFER DAC channel output buffer
  * @{
  */
#define LL_DAC_OUTPUT_BUFFER_ENABLE        0x00000000U             /*!< The selected DAC channel output is buffered: higher drive current capability, but also higher current consumption */
#define LL_DAC_OUTPUT_BUFFER_DISABLE       (DAC_CR_BOFF1)          /*!< The selected DAC channel output is not buffered: lower drive current capability, but also lower current consumption */

常用函数

  • 使能请求DMAvoid LL_DAC_EnableDMAReq(DAC_TypeDef *DACx, uint32_t DAC_Channel)
  • 获取寄存器地址uint32_t LL_DAC_DMA_GetRegAddr(DAC_TypeDef *DACx, uint32_t DAC_Channel, uint32_t Register)、
  • 使能DACvoid LL_DAC_Enable(DAC_TypeDef *DACx, uint32_t DAC_Channel)
  • 使能触发源void LL_DAC_EnableTrigger(DAC_TypeDef *DACx, uint32_t DAC_Channel)
  • 使能软件触发void LL_DAC_TrigSWConversion(DAC_TypeDef *DACx, uint32_t DAC_Channel)
  • 设置右对齐12位的转换数据void LL_DAC_ConvertData12RightAligned(DAC_TypeDef *DACx, uint32_t DAC_Channel, uint32_t Data)
  • 设置左对齐12位的转换数据void LL_DAC_ConvertData12LeftAligned(DAC_TypeDef *DACx, uint32_t DAC_Channel, uint32_t Data)
  • 设置右对齐8位的转换数据void LL_DAC_ConvertData8RightAligned(DAC_TypeDef *DACx, uint32_t DAC_Channel, uint32_t Data)
  • 设置右对齐12位的双通道转换数据void LL_DAC_ConvertDualData12RightAligned(DAC_TypeDef *DACx, uint32_t DataChannel1,uint32_t DataChannel2)
  • 设置左对齐12位的双通道转换数据void LL_DAC_ConvertDualData12LeftAligned(DAC_TypeDef *DACx, uint32_t DataChannel1,uint32_t DataChannel2)
  • 设置右对齐8位的双通道转换数据void LL_DAC_ConvertDualData8RightAligned(DAC_TypeDef *DACx, uint32_t DataChannel1,uint32_t DataChannel2)

代码移植

开始DAC转换

  • 在main.c文件添加变量
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//正弦波单个周期的点数
#define POINT_NUM 32

/* 波形数据 ---------------------------------------------------------*/
const uint16_t Sine12bit[POINT_NUM] = {
    2048,2460,2856,3218,3532,3786,3969,4072,
    4093,4031,3887,3668,3382,3042,2661,2255,
    1841,1435,1054,714,428,209,65,3,
    24,127,310,564,878,1240,1636,2048
};
uint32_t DualSine12bit[POINT_NUM];
  • 在主函数初始化添加DMA开始转换
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    uint32_t Idx;
    /* 填充正弦波形数据，双通道右对齐*/
    for (Idx = 0; Idx < POINT_NUM; Idx++)
    {
        DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);
    }
    LL_DMA_SetPeriphAddress(DMA2,LL_DMA_CHANNEL_4,(uint32_t)(&DAC->DHR12RD)); //设置外设地址，LL库只有单通道获取DMA地址的函数，所以我们直接取双通道的地址
    LL_DMA_SetMemoryAddress(DMA2,LL_DMA_CHANNEL_4,(uint32_t)DualSine12bit);//设置存储器地址
    LL_DMA_SetDataLength(DMA2,LL_DMA_CHANNEL_4,POINT_NUM);//设置传输长度
    LL_DMA_EnableChannel(DMA2,LL_DMA_CHANNEL_4);//使能DMA通道
    LL_DAC_Enable(DAC,LL_DAC_CHANNEL_1);//使能DAC通道1
    LL_DAC_Enable(DAC,LL_DAC_CHANNEL_2);//使能DAC通道2
    LL_DAC_EnableDMAReq(DAC,LL_DAC_CHANNEL_2);//使能通道2 DMA请求
    LL_TIM_EnableCounter(TIM2);//使能定时器

下载调试

  • 编译之后下载到开发板
  • 使用示波器查看PA4,PA5输出波形,为2K正弦波
  • 和HAL库结果一致