1. //========================================DAC=========================================
2. #define DA_OUT1_CHANNEL    DAC_Channel_1
3. #define DA_OUT1_GRP        GPIOA
4. #define DA_OUT1_INDEX      GPIO_Pin_4
5. #define DA_OUT1_HIGH()     GPIO_SetBits(DA_OUT1_GRP, DA_OUT1_INDEX)
6. #define DA_OUT1_CONFIG()   GPIOConfig(DA_OUT1_GRP, DA_OUT1_INDEX, GPIO_Mode_AIN)
7. #define DA_OUT2_CHANNEL    DAC_Channel_2
8. #define DA_OUT2_GRP        GPIOA
9. #define DA_OUT2_INDEX      GPIO_Pin_5
10. #define DA_OUT2_HIGH()     GPIO_SetBits(DA_OUT2_GRP, DA_OUT2_INDEX)
11. #define DA_OUT2_CONFIG()   GPIOConfig(DA_OUT2_GRP, DA_OUT2_INDEX, GPIO_Mode_AIN)

1. #ifndef _DAC_H_
2. #define _DAC_H_
3. void DAC1Init(void);  
4. void DAC1OutVoltage(float data);  
5. void DAC2Init(void);  
6. #endif /* _DAC_H_ */

1. #include "dac.h"
2. //#include "target.h"
3. #include "type.h"
4. #define DAC_DHR12RD_ADDRESS      0x40007420
5. staticconst uint16_t sin[32] =  
6. {  
7.   2047, 2447, 2831, 3185, 3498, 3750, 3939, 4056, 4095, 4056,  
8.   3939, 3750, 3495, 3185, 2831, 2447, 2047, 1647, 1263, 909,  
9.   599, 344, 155, 38, 0, 38, 155, 344, 599, 909, 1263, 1647  
10. };  
11. static uint32_t dual_sin[32];  
12. static uint8_t index = 0;  
13. // PA4
14. staticvoid dac1_clk_init(void)  
15. {  
16.   RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);  
17. }  
18. staticvoid dac1_gpio_init(void)  
19. {  
20.   DA_OUT1_CONFIG();  
21.   DA_OUT1_HIGH();  
22. }  
23. staticvoid dac1_mode_init(void)  
24. {  
25.   DAC_InitTypeDef DAC_InitStructure;  
26.   DAC_InitStructure.DAC_Trigger = DAC_Trigger_Software;  
27.   DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;  
28.   DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bits11_0;  
29.   DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;  
30.   DAC_Init(DA_OUT1_CHANNEL, &DAC_InitStructure);  
31.   DAC_Cmd(DA_OUT1_CHANNEL, ENABLE);  
32. }  
33. void DAC1Init(void)  
34. {  
35.   dac1_clk_init();  
36.   dac1_gpio_init();  
37.   dac1_mode_init();  
38. }  
39. // DAC1OutVoltage(1.5);// 1.5V out
40. void DAC1OutVoltage(float data)  
41. {  
42.   uint16_t value;  
43.   value = (uint16_t)((data / 3.3) * 4096);  
44.   DAC_SetChannel1Data(DAC_Align_12b_R, value);  
45.   DAC_SoftwareTriggerCmd(DA_OUT1_CHANNEL, ENABLE);  
46. }  
47. staticvoid dac2_clk_init(void)  
48. {  
49.   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA2, ENABLE);  
50.   RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);  
51.   RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);  
52. }  
53. staticvoid dac2_gpio_init(void)  
54. {  
55.   DA_OUT2_CONFIG();  
56.   DA_OUT2_HIGH();  
57. }  
58. staticvoid dac2_timer_init(void)  
59. {  
60.   TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;  
61.   TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);  
62.   TIM_TimeBaseStructure.TIM_Period = 0x19;  
63.   TIM_TimeBaseStructure.TIM_Prescaler = 0x0;  
64.   TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;  
65.   TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  
66.   TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);  
67.   /* TIM8 TRGO selection */
68.   TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update);  
69. }  
70. staticvoid dac2_mode_init(void)  
71. {  
72.   DAC_InitTypeDef DAC_InitStructure;  
73.   /* DAC channel2 Configuration */
74.   DAC_InitStructure.DAC_Trigger = DAC_Trigger_T8_TRGO;  
75.   DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;  
76.   DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;  
77.   DAC_Init(DA_OUT2_CHANNEL, &DAC_InitStructure);  
78.   for(index = 0; index < 32; ++index)  
79.   {  
80.     dual_sin[index] = (sin[index] << 16) + sin[index];  
81.   }  
82. }  
83. staticvoid dac2_dma_init(void)  
84. {  
85.   DMA_InitTypeDef DMA_InitStructure;  
86.   /* DMA2 channel4 configuration */
87.   DMA_DeInit(DMA2_Channel4);  
88.   DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12RD_ADDRESS;  
89.   DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&dual_sin;  
90.   DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;  
91.   DMA_InitStructure.DMA_BufferSize = 32;  
92.   DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;  
93.   DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;  
94.   DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;  
95.   DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;  
96.   DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;  
97.   DMA_InitStructure.DMA_Priority = DMA_Priority_High;  
98.   DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;  
99.   DMA_Init(DMA2_Channel4, &DMA_InitStructure);  
100. }  
101. staticvoid dac2_enable(void)  
102. {  
103.   DMA_Cmd(DMA2_Channel4, ENABLE);  
104.   DAC_Cmd(DA_OUT2_CHANNEL, ENABLE);  
105.   DAC_DMACmd(DA_OUT2_CHANNEL, ENABLE);  
106.   TIM_Cmd(TIM8, ENABLE);  
107. }  
108. void DAC2Init(void)  
109. {  
110.   dac2_clk_init();  
111.   dac2_gpio_init();  
112.   dac2_timer_init();  
113.   dac2_mode_init();  
114.   dac2_dma_init();  
115.   dac2_enable();  
116. }  

from：http://blog.csdn.net/wqx521/article/details/69468673