AT32 — 数模转换器 (DAC) on CLing

AT32 DAC — 单 DAC DMA 阶梯波

Tue, 08 Sep 2026 14:52:21 +0800

DAC — 单 DAC DMA 阶梯波

固件库: AT32F403A_407_Firmware_Library V2.2.2
芯片: AT32
源文件: AT32/AT32F403A_407_Firmware_Library_V2.2.2/project/at_start_f403a/examples/dac/one_dac_dma_escalator/src/main.c

功能简介

本示例演示 DAC 数模转换器的基本用法。DAC 将数字值转换为模拟电压输出，是生成模拟信号的关键外设。

完整代码

#include "at32f403a_407_board.h"
#include "at32f403a_407_clock.h"

int main(void)
{
  system_clock_config();

  at32_board_init();

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable dac/dma1/gpioa/tmr2 clock */
  crm_periph_clock_enable(CRM_TMR2_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_DMA1_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_DAC_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);

  /* once the dac is enabled, the corresponding gpio pin is automatically
     connected to the dac converter. in order to avoid parasitic consumption,
     the gpio pin should be configured in analog */
  gpio_init_struct.gpio_pins = GPIO_PINS_4 | GPIO_PINS_5;
  gpio_init_struct.gpio_mode = GPIO_MODE_ANALOG;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

  /* get system clock */
  crm_clocks_freq_get(&crm_clocks_freq_struct);

  /* (systemclock/(systemclock/1000000))/1000 = 1KHz */
  tmr_base_init(TMR2, 999, (crm_clocks_freq_struct.sclk_freq/1000000 - 1));
  tmr_cnt_dir_set(TMR2, TMR_COUNT_UP);

  /* primary tmr2 output selection */
  tmr_primary_mode_select(TMR2, TMR_PRIMARY_SEL_OVERFLOW);

  /* dac1 configuration */
  dac_trigger_select(DAC1_SELECT, DAC_TMR2_TRGOUT_EVENT);

  dac_trigger_enable(DAC1_SELECT, TRUE);

  dac_wave_generate(DAC1_SELECT, DAC_WAVE_GENERATE_NONE);

  dac_output_buffer_enable(DAC1_SELECT, FALSE);

  dac_dma_enable(DAC1_SELECT, TRUE);

  /* dma1 channel2 configuration */
  dma_reset(DMA1_CHANNEL2);
  dma_init_struct.buffer_size = 6;
  dma_init_struct.direction = DMA_DIR_MEMORY_TO_PERIPHERAL;
  dma_init_struct.memory_base_addr = (uint32_t)escalator8bit;
  dma_init_struct.memory_data_width = DMA_MEMORY_DATA_WIDTH_BYTE;
  dma_init_struct.memory_inc_enable = TRUE;
  dma_init_struct.peripheral_base_addr = (uint32_t)0x40007410;
  dma_init_struct.peripheral_data_width = DMA_PERIPHERAL_DATA_WIDTH_BYTE;
  dma_init_struct.peripheral_inc_enable = FALSE;
  dma_init_struct.priority = DMA_PRIORITY_MEDIUM;
  dma_init_struct.loop_mode_enable = TRUE;
  dma_init(DMA1_CHANNEL2, &dma_init_struct);

  /* enable dma flexible function */
  dma_flexible_config(DMA1, FLEX_CHANNEL2, DMA_FLEXIBLE_DAC1);

  dma_channel_enable(DMA1_CHANNEL2, TRUE);

  /* enable dac1: once the dac1 is enabled, pa.04 is
     automatically connected to the dac converter. */
  dac_enable(DAC1_SELECT, TRUE);

  /* enable tmr2 */
  tmr_counter_enable(TMR2, TRUE);
  while(1)
  {
  }
}

代码讲解

系统时钟初始化：配置 MCU 的主频和时钟树。不同芯片的时钟配置不同，一般由工具生成。

板级初始化：初始化开发板上的 LED、按键等基础外设。

GPIO 配置：设置引脚为输出/输入模式，选择推挽/开漏输出，配置上拉/下拉。

DMA 配置：设置源地址、目标地址、传输方向、数据宽度。DMA 搬运数据不占用 CPU。

定时器配置：设置预分频器（PSC）和重装载值（ARR），定时时间 = (PSC+1) × (ARR+1) / 时钟频率。

AT32 DAC — 单 DAC 噪声波

Tue, 08 Sep 2026 14:52:21 +0800

DAC — 单 DAC 噪声波

固件库: AT32F403A_407_Firmware_Library V2.2.2
芯片: AT32
源文件: AT32/AT32F403A_407_Firmware_Library_V2.2.2/project/at_start_f403a/examples/dac/one_dac_noisewave/src/main.c

功能简介

本示例演示 DAC 噪声波生成。利用 LFSR（线性反馈移位寄存器）生成伪噪声信号，可用于音频测试等场景。

完整代码

#include "at32f403a_407_board.h"
#include "at32f403a_407_clock.h"

int main(void)
{
  system_clock_config();

  at32_board_init();

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable dac/gpioa clock */
  crm_periph_clock_enable(CRM_DAC_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);

  /* once the dac is enabled, the corresponding gpio pin is automatically
     connected to the dac converter. in order to avoid parasitic consumption,
     the gpio pin should be configured in analog */
  gpio_init_struct.gpio_pins = GPIO_PINS_4;
  gpio_init_struct.gpio_mode = GPIO_MODE_ANALOG;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

  /* dac1 configuration */
  dac_trigger_select(DAC1_SELECT, DAC_SOFTWARE_TRIGGER);

  dac_trigger_enable(DAC1_SELECT, TRUE);

  dac_wave_generate(DAC1_SELECT, DAC_WAVE_GENERATE_NOISE);

  dac_mask_amplitude_select(DAC1_SELECT, DAC_LSFR_BITB0_AMPLITUDE_4095);

  dac_output_buffer_enable(DAC1_SELECT, TRUE);

  /* enable dac1: once the dac1 is enabled, pa.04 is
     automatically connected to the dac converter. */
  dac_enable(DAC1_SELECT, TRUE);

  while(1)
  {
    dac_software_trigger_generate(DAC1_SELECT);
    delay_us(1);
  }
}

代码讲解

系统时钟初始化：配置 MCU 的主频和时钟树。不同芯片的时钟配置不同，一般由工具生成。

板级初始化：初始化开发板上的 LED、按键等基础外设。

GPIO 配置：设置引脚为输出/输入模式，选择推挽/开漏输出，配置上拉/下拉。

AT32 DAC — 双 DAC 三角波

Tue, 08 Sep 2026 14:52:21 +0800

DAC — 双 DAC 三角波

固件库: AT32F403A_407_Firmware_Library V2.2.2
芯片: AT32
源文件: AT32/AT32F403A_407_Firmware_Library_V2.2.2/project/at_start_f403a/examples/dac/two_dac_trianglewave/src/main.c

功能简介

本示例演示 DAC 输出三角波。利用 DAC 内置的三角波生成器，无需 CPU 干预即可输出三角波。

完整代码

#include "at32f403a_407_board.h"
#include "at32f403a_407_clock.h"

int main(void)
{
  system_clock_config();

  at32_board_init();

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable dac/tmr2/gpioa clock */
  crm_periph_clock_enable(CRM_DAC_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_TMR2_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);

  /* once the dac is enabled, the corresponding gpio pin is automatically
     connected to the dac converter. in order to avoid parasitic consumption,
     the gpio pin should be configured in analog */
  gpio_init_struct.gpio_pins = GPIO_PINS_4 | GPIO_PINS_5;
  gpio_init_struct.gpio_mode = GPIO_MODE_ANALOG;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

  /* get system clock */
  crm_clocks_freq_get(&crm_clocks_freq_struct);

  /* (systemclock/(systemclock/1000000))/100 = 10KHz */
  tmr_base_init(TMR2, 99, (crm_clocks_freq_struct.sclk_freq/1000000 - 1));
  tmr_cnt_dir_set(TMR2, TMR_COUNT_UP);

  /* primary tmr2 output selection */
  tmr_primary_mode_select(TMR2, TMR_PRIMARY_SEL_OVERFLOW);

  /* dac1 and dac2 configuration */
  dac_trigger_select(DAC1_SELECT, DAC_TMR2_TRGOUT_EVENT);
  dac_trigger_select(DAC2_SELECT, DAC_TMR2_TRGOUT_EVENT);

  dac_trigger_enable(DAC1_SELECT, TRUE);
  dac_trigger_enable(DAC2_SELECT, TRUE);

  dac_wave_generate(DAC1_SELECT, DAC_WAVE_GENERATE_TRIANGLE);
  dac_wave_generate(DAC2_SELECT, DAC_WAVE_GENERATE_TRIANGLE);

  dac_mask_amplitude_select(DAC1_SELECT, DAC_LSFR_BIT90_AMPLITUDE_1023);
  dac_mask_amplitude_select(DAC2_SELECT, DAC_LSFR_BITA0_AMPLITUDE_2047);

  dac_output_buffer_enable(DAC1_SELECT, FALSE);
  dac_output_buffer_enable(DAC2_SELECT, FALSE);

  dac_dma_enable(DAC1_SELECT, TRUE);
  dac_dma_enable(DAC2_SELECT, TRUE);

  /* enable dac1: once the dac1 is enabled, pa.04 is
     automatically connected to the dac converter. */
  dac_enable(DAC1_SELECT, TRUE);

  /* enable dac2: once the dac2 is enabled, pa.05 is
     automatically connected to the dac converter. */
  dac_enable(DAC2_SELECT, TRUE);

  dac_dual_data_set(DAC_DUAL_12BIT_RIGHT, 0x100, 0x100);

  /* enable tmr2 */
  tmr_counter_enable(TMR2, TRUE);

  while(1)
  {
  }
}

代码讲解

系统时钟初始化：配置 MCU 的主频和时钟树。不同芯片的时钟配置不同，一般由工具生成。

板级初始化：初始化开发板上的 LED、按键等基础外设。

GPIO 配置：设置引脚为输出/输入模式，选择推挽/开漏输出，配置上拉/下拉。

定时器配置：设置预分频器（PSC）和重装载值（ARR），定时时间 = (PSC+1) × (ARR+1) / 时钟频率。

AT32 DAC — 双通道 DMA 方波

Tue, 08 Sep 2026 14:52:21 +0800

DAC — 双通道 DMA 方波

固件库: AT32F403A_407_Firmware_Library V2.2.2
芯片: AT32
源文件: AT32/AT32F403A_407_Firmware_Library_V2.2.2/project/at_start_f403a/examples/dac/double_mode_dma_squarewave/src/main.c

功能简介

本示例演示 DAC 数模转换器的基本用法。DAC 将数字值转换为模拟电压输出，是生成模拟信号的关键外设。

完整代码

#include "at32f403a_407_board.h"
#include "at32f403a_407_clock.h"

int main(void)
{
  system_clock_config();

  at32_board_init();

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable dac/dma1/gpioa clock */
  crm_periph_clock_enable(CRM_DMA1_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_DAC_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);

  /* once the dac is enabled, the corresponding gpio pin is automatically
     connected to the dac converter. in order to avoid parasitic consumption,
     the gpio pin should be configured in analog */
  gpio_init_struct.gpio_pins = GPIO_PINS_4 | GPIO_PINS_5;
  gpio_init_struct.gpio_mode = GPIO_MODE_ANALOG;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

  /* dac1 and dac2 configuration */
  dac_trigger_select(DAC1_SELECT, DAC_SOFTWARE_TRIGGER);
  dac_trigger_select(DAC2_SELECT, DAC_SOFTWARE_TRIGGER);

  dac_trigger_enable(DAC1_SELECT, TRUE);
  dac_trigger_enable(DAC2_SELECT, TRUE);

  dac_wave_generate(DAC1_SELECT, DAC_WAVE_GENERATE_NONE);
  dac_wave_generate(DAC2_SELECT, DAC_WAVE_GENERATE_NONE);

  dac_output_buffer_enable(DAC1_SELECT, TRUE);
  dac_output_buffer_enable(DAC2_SELECT, TRUE);

  dac_dma_enable(DAC1_SELECT, TRUE);
  dac_dma_enable(DAC2_SELECT, TRUE);

  /* dma1 channel1 configuration */
  dma_reset(DMA1_CHANNEL1);
  dma_init_struct.buffer_size = 2;
  dma_init_struct.direction = DMA_DIR_MEMORY_TO_PERIPHERAL;
  dma_init_struct.memory_base_addr = (uint32_t)dualsquare12bit;
  dma_init_struct.memory_data_width = DMA_MEMORY_DATA_WIDTH_WORD;
  dma_init_struct.memory_inc_enable = TRUE;
  dma_init_struct.peripheral_base_addr = (uint32_t)0x40007420;
  dma_init_struct.peripheral_data_width = DMA_PERIPHERAL_DATA_WIDTH_WORD;
  dma_init_struct.peripheral_inc_enable = FALSE;
  dma_init_struct.priority = DMA_PRIORITY_MEDIUM;
  dma_init_struct.loop_mode_enable = TRUE;
  dma_init(DMA1_CHANNEL1, &dma_init_struct);

  /* enable dma flexible function */
  dma_flexible_config(DMA1, FLEX_CHANNEL1, DMA_FLEXIBLE_DAC2);

  dma_channel_enable(DMA1_CHANNEL1, TRUE);

  /* enable dac1: once the dac1 is enabled, pa.04 is
     automatically connected to the dac converter. */
  dac_enable(DAC1_SELECT, TRUE);

  /* enable dac2: once the dac2 is enabled, pa.05 is
     automatically connected to the dac converter. */
  dac_enable(DAC2_SELECT, TRUE);

  while(1)
  {
    delay_us(100);
    dac_software_trigger_generate(DAC1_SELECT);
    dac_software_trigger_generate(DAC2_SELECT);
  }
}

代码讲解

系统时钟初始化：配置 MCU 的主频和时钟树。不同芯片的时钟配置不同，一般由工具生成。

板级初始化：初始化开发板上的 LED、按键等基础外设。

GPIO 配置：设置引脚为输出/输入模式，选择推挽/开漏输出，配置上拉/下拉。

DMA 配置：设置源地址、目标地址、传输方向、数据宽度。DMA 搬运数据不占用 CPU。

AT32 DAC — 双通道 DMA 正弦波

Tue, 08 Sep 2026 14:52:21 +0800

DAC — 双通道 DMA 正弦波

固件库: AT32F403A_407_Firmware_Library V2.2.2
芯片: AT32
源文件: AT32/AT32F403A_407_Firmware_Library_V2.2.2/project/at_start_f403a/examples/dac/double_mode_dma_sinewave/src/main.c

功能简介

本示例演示 DAC 输出正弦波。通过 DMA 自动将正弦波数据表送到 DAC，可以生成指定频率的模拟正弦信号。

完整代码

#include "at32f403a_407_board.h"
#include "at32f403a_407_clock.h"

int main(void)
{
  system_clock_config();

  at32_board_init();

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable dac/tmr2/gpioa clock */
  crm_periph_clock_enable(CRM_DMA1_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_DAC_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_TMR2_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);

  /* once the dac is enabled, the corresponding gpio pin is automatically
     connected to the dac converter. in order to avoid parasitic consumption,
     the gpio pin should be configured in analog */
  gpio_init_struct.gpio_pins = GPIO_PINS_4 | GPIO_PINS_5;
  gpio_init_struct.gpio_mode = GPIO_MODE_ANALOG;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

  /* get system clock */
  crm_clocks_freq_get(&crm_clocks_freq_struct);

  /* (systemclock/(systemclock/1000000))/100 = 10KHz */
  tmr_base_init(TMR2, 99, (crm_clocks_freq_struct.sclk_freq/1000000 - 1));
  tmr_cnt_dir_set(TMR2, TMR_COUNT_UP);

  /* primary tmr2 output selection */
  tmr_primary_mode_select(TMR2, TMR_PRIMARY_SEL_OVERFLOW);

  /* dac1 and dac2 configuration */
  dac_trigger_select(DAC1_SELECT, DAC_TMR2_TRGOUT_EVENT);
  dac_trigger_select(DAC2_SELECT, DAC_TMR2_TRGOUT_EVENT);

  dac_trigger_enable(DAC1_SELECT, TRUE);
  dac_trigger_enable(DAC2_SELECT, TRUE);

  dac_wave_generate(DAC1_SELECT, DAC_WAVE_GENERATE_NONE);
  dac_wave_generate(DAC2_SELECT, DAC_WAVE_GENERATE_NONE);

  dac_output_buffer_enable(DAC1_SELECT, FALSE);
  dac_output_buffer_enable(DAC2_SELECT, FALSE);

  dac_dma_enable(DAC1_SELECT, TRUE);
  dac_dma_enable(DAC2_SELECT, TRUE);

  /* fill sine32bit table */
  for(idx = 0; idx < 32; idx++)
  {
    dualsine12bit[idx] = (sine12bit[idx] << 16) + (sine12bit[idx]);
  }

  /* dma1 channel1 configuration */
  dma_reset(DMA1_CHANNEL1);
  dma_init_struct.buffer_size = 32;
  dma_init_struct.direction = DMA_DIR_MEMORY_TO_PERIPHERAL;
  dma_init_struct.memory_base_addr = (uint32_t)dualsine12bit;
  dma_init_struct.memory_data_width = DMA_MEMORY_DATA_WIDTH_WORD;
  dma_init_struct.memory_inc_enable = TRUE;
  dma_init_struct.peripheral_base_addr = (uint32_t)0x40007420;
  dma_init_struct.peripheral_data_width = DMA_PERIPHERAL_DATA_WIDTH_WORD;
  dma_init_struct.peripheral_inc_enable = FALSE;
  dma_init_struct.priority = DMA_PRIORITY_MEDIUM;
  dma_init_struct.loop_mode_enable = TRUE;
  dma_init(DMA1_CHANNEL1, &dma_init_struct);

  /* enable dma flexible function */
  dma_flexible_config(DMA1, FLEX_CHANNEL1, DMA_FLEXIBLE_DAC2);

  dma_channel_enable(DMA1_CHANNEL1, TRUE);

  /* enable dac1: once the dac1 is enabled, pa.04 is
     automatically connected to the dac converter. */
  dac_enable(DAC1_SELECT, TRUE);

  /* enable dac2: once the dac2 is enabled, pa.05 is
     automatically connected to the dac converter. */
  dac_enable(DAC2_SELECT, TRUE);

  /* enable tmr2 */
  tmr_counter_enable(TMR2, TRUE);

  while(1)
  {
  }
}

代码讲解

系统时钟初始化：配置 MCU 的主频和时钟树。不同芯片的时钟配置不同，一般由工具生成。

板级初始化：初始化开发板上的 LED、按键等基础外设。

GPIO 配置：设置引脚为输出/输入模式，选择推挽/开漏输出，配置上拉/下拉。

DMA 配置：设置源地址、目标地址、传输方向、数据宽度。DMA 搬运数据不占用 CPU。

定时器配置：设置预分频器（PSC）和重装载值（ARR），定时时间 = (PSC+1) × (ARR+1) / 时钟频率。