00. 目录
01. DAC简介
STM32F4的DAC模块(数字/模拟转换模块)是12位数字输入，电压输出型的DAC。DAC可以配置为 8 位或 12 位模式，也可以与 DMA 控制器配合使用。DAC 工作在 12 位模式时，数据可以设置成左对齐或右对齐。DAC 模块有 2 个输出通道，每个通道都有单独的转换器。在双 DAC 模式下，2 个通道可以独立地进行转换，也可以同时进行转换并同步地更新 2 个通道的输出。DAC 可以通过引脚输入参考电压 Vref+（通 ADC 共用）以获得更精确的转换结果。
STM32F4 的 DAC 模块主要特点有：
① 2 个 DAC 转换器：每个转换器对应 1 个输出通道
② 8 位或者 12 位单调输出
③ 12 位模式下数据左对齐或者右对齐
④ 同步更新功能
⑤ 噪声波形生成
⑥ 三角波形生成
⑦ 双 DAC 通道同时或者分别转换
⑧ 每个通道都有 DMA 功能
02. 相关类型
DAC Init structure
/**
* @brief DAC Init structure definition
*/
typedef struct
{
uint32_t DAC_Trigger; /*!< Specifies the external trigger for the selected DAC channel.
This parameter can be a value of @ref DAC_trigger_selection */
uint32_t DAC_WaveGeneration; /*!< Specifies whether DAC channel noise waves or triangle waves
are generated, or whether no wave is generated.
This parameter can be a value of @ref DAC_wave_generation */
uint32_t DAC_LFSRUnmask_TriangleAmplitude; /*!< Specifies the LFSR mask for noise wave generation or
the maximum amplitude triangle generation for the DAC channel.
This parameter can be a value of @ref DAC_lfsrunmask_triangleamplitude */
uint32_t DAC_OutputBuffer; /*!< Specifies whether the DAC channel output buffer is enabled or disabled.
This parameter can be a value of @ref DAC_output_buffer */
}DAC_InitTypeDef;
DAC_trigger_selection
/** @defgroup DAC_trigger_selection
* @{
*/
#define DAC_Trigger_None ((uint32_t)0x00000000) /*!< Conversion is automatic once the DAC1_DHRxxxx register
has been loaded, and not by external trigger */
#define DAC_Trigger_T2_TRGO ((uint32_t)0x00000024) /*!< TIM2 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_T4_TRGO ((uint32_t)0x0000002C) /*!< TIM4 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_T5_TRGO ((uint32_t)0x0000001C) /*!< TIM5 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_T6_TRGO ((uint32_t)0x00000004) /*!< TIM6 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_T7_TRGO ((uint32_t)0x00000014) /*!< TIM7 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_T8_TRGO ((uint32_t)0x0000000C) /*!< TIM8 TRGO selected as external conversion trigger for DAC channel */
#define DAC_Trigger_Ext_IT9 ((uint32_t)0x00000034) /*!< EXTI Line9 event selected as external conversion trigger for DAC channel */
#define DAC_Trigger_Software ((uint32_t)0x0000003C) /*!< Conversion started by software trigger for DAC channel */
#define IS_DAC_TRIGGER(TRIGGER) (((TRIGGER) == DAC_Trigger_None) || \
((TRIGGER) == DAC_Trigger_T6_TRGO) || \
((TRIGGER) == DAC_Trigger_T8_TRGO) || \
((TRIGGER) == DAC_Trigger_T7_TRGO) || \
((TRIGGER) == DAC_Trigger_T5_TRGO) || \
((TRIGGER) == DAC_Trigger_T2_TRGO) || \
((TRIGGER) == DAC_Trigger_T4_TRGO) || \
((TRIGGER) == DAC_Trigger_Ext_IT9) || \
((TRIGGER) == DAC_Trigger_Software))
DAC_wave_generation
/** @defgroup DAC_wave_generation
* @{
*/
#define DAC_WaveGeneration_None ((uint32_t)0x00000000)
#define DAC_WaveGeneration_Noise ((uint32_t)0x00000040)
#define DAC_WaveGeneration_Triangle ((uint32_t)0x00000080)
#define IS_DAC_GENERATE_WAVE(WAVE) (((WAVE) == DAC_WaveGeneration_None) || \
((WAVE) == DAC_WaveGeneration_Noise) || \
((WAVE) == DAC_WaveGeneration_Triangle))
DAC_lfsrunmask_triangleamplitude
/** @defgroup DAC_lfsrunmask_triangleamplitude
* @{
*/
#define DAC_LFSRUnmask_Bit0 ((uint32_t)0x00000000) /*!< Unmask DAC channel LFSR bit0 for noise wave generation */
#define DAC_LFSRUnmask_Bits1_0 ((uint32_t)0x00000100) /*!< Unmask DAC channel LFSR bit[1:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits2_0 ((uint32_t)0x00000200) /*!< Unmask DAC channel LFSR bit[2:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits3_0 ((uint32_t)0x00000300) /*!< Unmask DAC channel LFSR bit[3:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits4_0 ((uint32_t)0x00000400) /*!< Unmask DAC channel LFSR bit[4:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits5_0 ((uint32_t)0x00000500) /*!< Unmask DAC channel LFSR bit[5:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits6_0 ((uint32_t)0x00000600) /*!< Unmask DAC channel LFSR bit[6:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits7_0 ((uint32_t)0x00000700) /*!< Unmask DAC channel LFSR bit[7:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits8_0 ((uint32_t)0x00000800) /*!< Unmask DAC channel LFSR bit[8:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits9_0 ((uint32_t)0x00000900) /*!< Unmask DAC channel LFSR bit[9:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits10_0 ((uint32_t)0x00000A00) /*!< Unmask DAC channel LFSR bit[10:0] for noise wave generation */
#define DAC_LFSRUnmask_Bits11_0 ((uint32_t)0x00000B00) /*!< Unmask DAC channel LFSR bit[11:0] for noise wave generation */
#define DAC_TriangleAmplitude_1 ((uint32_t)0x00000000) /*!< Select max triangle amplitude of 1 */
#define DAC_TriangleAmplitude_3 ((uint32_t)0x00000100) /*!< Select max triangle amplitude of 3 */
#define DAC_TriangleAmplitude_7 ((uint32_t)0x00000200) /*!< Select max triangle amplitude of 7 */
#define DAC_TriangleAmplitude_15 ((uint32_t)0x00000300) /*!< Select max triangle amplitude of 15 */
#define DAC_TriangleAmplitude_31 ((uint32_t)0x00000400) /*!< Select max triangle amplitude of 31 */
#define DAC_TriangleAmplitude_63 ((uint32_t)0x00000500) /*!< Select max triangle amplitude of 63 */
#define DAC_TriangleAmplitude_127 ((uint32_t)0x00000600) /*!< Select max triangle amplitude of 127 */
#define DAC_TriangleAmplitude_255 ((uint32_t)0x00000700) /*!< Select max triangle amplitude of 255 */
#define DAC_TriangleAmplitude_511 ((uint32_t)0x00000800) /*!< Select max triangle amplitude of 511 */
#define DAC_TriangleAmplitude_1023 ((uint32_t)0x00000900) /*!< Select max triangle amplitude of 1023 */
#define DAC_TriangleAmplitude_2047 ((uint32_t)0x00000A00) /*!< Select max triangle amplitude of 2047 */
#define DAC_TriangleAmplitude_4095 ((uint32_t)0x00000B00) /*!< Select max triangle amplitude of 4095 */
#define IS_DAC_LFSR_UNMASK_TRIANGLE_AMPLITUDE(VALUE) (((VALUE) == DAC_LFSRUnmask_Bit0) || \
((VALUE) == DAC_LFSRUnmask_Bits1_0) || \
((VALUE) == DAC_LFSRUnmask_Bits2_0) || \
((VALUE) == DAC_LFSRUnmask_Bits3_0) || \
((VALUE) == DAC_LFSRUnmask_Bits4_0) || \
((VALUE) == DAC_LFSRUnmask_Bits5_0) || \
((VALUE) == DAC_LFSRUnmask_Bits6_0) || \
((VALUE) == DAC_LFSRUnmask_Bits7_0) || \
((VALUE) == DAC_LFSRUnmask_Bits8_0) || \
((VALUE) == DAC_LFSRUnmask_Bits9_0) || \
((VALUE) == DAC_LFSRUnmask_Bits10_0) || \
((VALUE) == DAC_LFSRUnmask_Bits11_0) || \
((VALUE) == DAC_TriangleAmplitude_1) || \
((VALUE) == DAC_TriangleAmplitude_3) || \
((VALUE) == DAC_TriangleAmplitude_7) || \
((VALUE) == DAC_TriangleAmplitude_15) || \
((VALUE) == DAC_TriangleAmplitude_31) || \
((VALUE) == DAC_TriangleAmplitude_63) || \
((VALUE) == DAC_TriangleAmplitude_127) || \
((VALUE) == DAC_TriangleAmplitude_255) || \
((VALUE) == DAC_TriangleAmplitude_511) || \
((VALUE) == DAC_TriangleAmplitude_1023) || \
((VALUE) == DAC_TriangleAmplitude_2047) || \
((VALUE) == DAC_TriangleAmplitude_4095))
DAC_output_buffer
/** @defgroup DAC_output_buffer
* @{
*/
#define DAC_OutputBuffer_Enable ((uint32_t)0x00000000)
#define DAC_OutputBuffer_Disable ((uint32_t)0x00000002)
#define IS_DAC_OUTPUT_BUFFER_STATE(STATE) (((STATE) == DAC_OutputBuffer_Enable) || \
((STATE) == DAC_OutputBuffer_Disable))
DAC_Channel_selection
/** @defgroup DAC_Channel_selection
* @{
*/
#define DAC_Channel_1 ((uint32_t)0x00000000)
#define DAC_Channel_2 ((uint32_t)0x00000010)
#define IS_DAC_CHANNEL(CHANNEL) (((CHANNEL) == DAC_Channel_1) || \
((CHANNEL) == DAC_Channel_2))
DAC_data_alignement
/** @defgroup DAC_data_alignement
* @{
*/
#define DAC_Align_12b_R ((uint32_t)0x00000000)
#define DAC_Align_12b_L ((uint32_t)0x00000004)
#define DAC_Align_8b_R ((uint32_t)0x00000008)
#define IS_DAC_ALIGN(ALIGN) (((ALIGN) == DAC_Align_12b_R) || \
((ALIGN) == DAC_Align_12b_L) || \
((ALIGN) == DAC_Align_8b_R))
DAC_wave_generation
/** @defgroup DAC_wave_generation
* @{
*/
#define DAC_Wave_Noise ((uint32_t)0x00000040)
#define DAC_Wave_Triangle ((uint32_t)0x00000080)
#define IS_DAC_WAVE(WAVE) (((WAVE) == DAC_Wave_Noise) || \
((WAVE) == DAC_Wave_Triangle))
其它
/** @defgroup DAC_data
* @{
*/
#define IS_DAC_DATA(DATA) ((DATA) <= 0xFFF0)
/**
* @}
*/
/** @defgroup DAC_interrupts_definition
* @{
*/
#define DAC_IT_DMAUDR ((uint32_t)0x00002000)
#define IS_DAC_IT(IT) (((IT) == DAC_IT_DMAUDR))
/**
* @}
*/
/** @defgroup DAC_flags_definition
* @{
*/
#define DAC_FLAG_DMAUDR ((uint32_t)0x00002000)
#define IS_DAC_FLAG(FLAG) (((FLAG) == DAC_FLAG_DMAUDR))
03. 相关函数
/* Function used to set the DAC configuration to the default reset state *****/
void DAC_DeInit(void);
/* DAC channels configuration: trigger, output buffer, data format functions */
void DAC_Init(uint32_t DAC_Channel, DAC_InitTypeDef* DAC_InitStruct);
void DAC_StructInit(DAC_InitTypeDef* DAC_InitStruct);
void DAC_Cmd(uint32_t DAC_Channel, FunctionalState NewState);
void DAC_SoftwareTriggerCmd(uint32_t DAC_Channel, FunctionalState NewState);
void DAC_DualSoftwareTriggerCmd(FunctionalState NewState);
void DAC_WaveGenerationCmd(uint32_t DAC_Channel, uint32_t DAC_Wave, FunctionalState NewState);
void DAC_SetChannel1Data(uint32_t DAC_Align, uint16_t Data);
void DAC_SetChannel2Data(uint32_t DAC_Align, uint16_t Data);
void DAC_SetDualChannelData(uint32_t DAC_Align, uint16_t Data2, uint16_t Data1);
uint16_t DAC_GetDataOutputValue(uint32_t DAC_Channel);
/* DMA management functions ***************************************************/
void DAC_DMACmd(uint32_t DAC_Channel, FunctionalState NewState);
/* Interrupts and flags management functions **********************************/
void DAC_ITConfig(uint32_t DAC_Channel, uint32_t DAC_IT, FunctionalState NewState);
FlagStatus DAC_GetFlagStatus(uint32_t DAC_Channel, uint32_t DAC_FLAG);
void DAC_ClearFlag(uint32_t DAC_Channel, uint32_t DAC_FLAG);
ITStatus DAC_GetITStatus(uint32_t DAC_Channel, uint32_t DAC_IT);
void DAC_ClearITPendingBit(uint32_t DAC_Channel, uint32_t DAC_IT);
04. 结构体封装
/**
* @brief Digital to Analog Converter
*/
typedef struct
{
__IO uint32_t CR; /*!< DAC control register, Address offset: 0x00 */
__IO uint32_t SWTRIGR; /*!< DAC software trigger register, Address offset: 0x04 */
__IO uint32_t DHR12R1; /*!< DAC channel1 12-bit right-aligned data holding register, Address offset: 0x08 */
__IO uint32_t DHR12L1; /*!< DAC channel1 12-bit left aligned data holding register, Address offset: 0x0C */
__IO uint32_t DHR8R1; /*!< DAC channel1 8-bit right aligned data holding register, Address offset: 0x10 */
__IO uint32_t DHR12R2; /*!< DAC channel2 12-bit right aligned data holding register, Address offset: 0x14 */
__IO uint32_t DHR12L2; /*!< DAC channel2 12-bit left aligned data holding register, Address offset: 0x18 */
__IO uint32_t DHR8R2; /*!< DAC channel2 8-bit right-aligned data holding register, Address offset: 0x1C */
__IO uint32_t DHR12RD; /*!< Dual DAC 12-bit right-aligned data holding register, Address offset: 0x20 */
__IO uint32_t DHR12LD; /*!< DUAL DAC 12-bit left aligned data holding register, Address offset: 0x24 */
__IO uint32_t DHR8RD; /*!< DUAL DAC 8-bit right aligned data holding register, Address offset: 0x28 */
__IO uint32_t DOR1; /*!< DAC channel1 data output register, Address offset: 0x2C */
__IO uint32_t DOR2; /*!< DAC channel2 data output register, Address offset: 0x30 */
__IO uint32_t SR; /*!< DAC status register, Address offset: 0x34 */
} DAC_TypeDef;
05. 预留
06. 附录
6.1 【STM32】STM32系列教程汇总
07. 声明
STM32F4xx英文参考手册