正弦波发生 频率可调

{
while(GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0)==0) ;
if(fre>2)
{
fre=fre-2;
}
}
if(GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_8)==0) //如果 PA8 = 0 {
while(GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_8)==0) ; if (fre<20) { fre=fre+2; }
/* Private define ---------------------------------------------------------_Address
0x40007420
#define
pi
3.14159265358979323846264338327950288419716939937510582097494459230781640628620
int main(void)
{
#ifdef DEBUG debug();
#endif /* System Clocks Configuration */ RCC_Configuration(); /* GPIO configuration */ GPIO_Configuration(); /* NVIC Configuration */ NVIC_Configuration(); /* TIM8 Configuration */
DAC_InitStructure.DAC_Trigger = DAC_Trigger_T8_TRGO; DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None; DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable; DAC_Init(DAC_Channel_1, &DAC_InitStructure);
TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure); /* TIM8 TRGO selection */
TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update); /* DAC channel1 Configuration */ DAC_StructInit(&DAC_InitStructure);
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{ /* Enable Prefetch Buffer */ FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable); /* Flash 2 wait state */ FLASH_SetLatency(FLASH_Latency_2); /* HCLK = SYSCLK */
/******************** (C) COPYRIGHT 2008 STMicroelectronics ******************** /
/* Includes ------------------------------------------------------------------*/
/* DAC channel2 Configuration */ DAC_Init(DAC_Channel_2, &DAC_InitStructure); /* Fill Sine32bit table */
/* DMA2 channel4 configuration */
DMA_DeInit(DMA2_Channel4); //DAC 通道 2 DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR12RD_Address; DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&sina ; // DualSine12bit sina DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; DMA_InitStructure.DMA_BufferSize = 32; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; DMA_Init(DMA2_Channel4, &DMA_InitStructure);
89986280348253421170679
/* Init Structure definition */
DAC_InitTypeDef
DAC_InitStructure;
DMA_InitTypeDef
DMA_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
void RCC_Configuration(void) {
/* RCC system reset(for debug purpose) */ RCC_DeInit(); /* Enable HSE */ RCC_HSEConfig(RCC_HSE_ON); /* Wait till HSE is ready */
/* TIM8 enable counter */ TIM_Cmd(TIM8, ENABLE);
}
}
/****************************************************************************** *
* Function Name : RCC_Configuration
#include "stm32f10x_lib.h" #include "math.h" #include "platform_config.h"
/* Private typedef -----------------------------------------------------------*/
//data format
/* for (Idx= 0; Idx<32; Idx++)
{
DualSine12bit[Idx] = (Sine12bit[Idx] << 16) + (Sine12bit[Idx]);
//16
} */
while(1)
{
if(GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0)==0) //如果 PA0 = 0
ErrorStatus HSEStartUpStatus;
/* uc16 Sine12bit[32] = {2047, 2447, 2831, 3185, 3498, 3750, 3939, 4056, 4095, 4056,
3939, 3750, 3495, 3185, 2831, 2447, 2047, 1647, 1263, 909, 599, 344, 155, 38, 0, 38, 155, 344, 599, 909, 1263, 1647}; */ u32 DualSine12bit[32]; u32 sina[32]; u32 sinb[32];
* Function Name : main
* Description : Main program.
* Input
: None
* Output
: None
* Return
: None
******************************************************************************* /
/* Enable DMA2 Channel4 */
DMA_Cmd(DMA2_Channel4, ENABLE); DMA_Cmd(DMA2_Channel3, ENABLE); /* Enable DAC Channel1 */ DAC_Cmd(DAC_Channel_1, ENABLE); /* Enable DAC Channel2 */ DAC_Cmd(DAC_Channel_2, ENABLE); /* Enable DMA for DAC Channel2 */ DAC_DMACmd(DAC_Channel_2, ENABLE);
* Description : Configures the different system clocks.
* Input
: None
* Output
: None
* Return
: None
******************************************************************************* /