STM32：DMA
1 DMA
DMA全称direct memory access，直接 内存 存取 外设；
作用：提供外设与存储器、存储器与存储器之间的高速数据传输；
特点：不占用CPU资源,能够大量高速处理数据提高效率；
flash(代码运行区)，SRAM，AHB，APB1，APB2外设均可作为访问的源或目标；
DMA外设和cortex-M3核心共享D-code总线矩阵，所以DMA才哪哪都可以访问(还没哪里是D-code总线到不了的)；
2 DMA寄存器
HFIF、CHTIF、HTIE这三个标志位有点离谱，到底是什么离谱的协议需要判断是否传输到一半然后停下来呢？埋个小雷期待一下；
2.1 DMA外设的通道选择
当dma传输数据[mem2men]使能的话，数据从内存传输到内存，每个通道都可以使用；
默认dma1的优先级高于dma2的优先级，channel_1的优先级高于channel_2的优先级；也可以在PL[13:12]中设置通道优先级；
3 DMA代码
3.1 寄存器封装
stm32f10x.h
typedef struct
{
__IO uint32_t CCR;
__IO uint32_t CNDTR;
__IO uint32_t CPAR;
__IO uint32_t CMAR;
} DMA_Channel_TypeDef;
typedef struct
{
__IO uint32_t ISR;
__IO uint32_t IFCR;
} DMA_TypeDef;
#define DMA1_BASE (AHBPERIPH_BASE + 0x0000)
#define DMA1_Channel1_BASE (AHBPERIPH_BASE + 0x0008)
#define DMA1_Channel2_BASE (AHBPERIPH_BASE + 0x001C)
#define DMA1_Channel3_BASE (AHBPERIPH_BASE + 0x0030)
#define DMA1_Channel4_BASE (AHBPERIPH_BASE + 0x0044)
#define DMA1_Channel5_BASE (AHBPERIPH_BASE + 0x0058)
#define DMA1_Channel6_BASE (AHBPERIPH_BASE + 0x006C)
#define DMA1_Channel7_BASE (AHBPERIPH_BASE + 0x0080)
#define DMA2_BASE (AHBPERIPH_BASE + 0x0400)
#define DMA2_Channel1_BASE (AHBPERIPH_BASE + 0x0408)
#define DMA2_Channel2_BASE (AHBPERIPH_BASE + 0x041C)
#define DMA2_Channel3_BASE (AHBPERIPH_BASE + 0x0430)
#define DMA2_Channel4_BASE (AHBPERIPH_BASE + 0x0444)
#define DMA2_Channel5_BASE (AHBPERIPH_BASE + 0x0458)
#define DMA1 ((DMA_TypeDef *) DMA1_BASE)
#define DMA2 ((DMA_TypeDef *) DMA2_BASE)
#define DMA1_Channel1 ((DMA_Channel_TypeDef *) DMA1_Channel1_BASE)
#define DMA1_Channel2 ((DMA_Channel_TypeDef *) DMA1_Channel2_BASE)
#define DMA1_Channel3 ((DMA_Channel_TypeDef *) DMA1_Channel3_BASE)
#define DMA1_Channel4 ((DMA_Channel_TypeDef *) DMA1_Channel4_BASE)
#define DMA1_Channel5 ((DMA_Channel_TypeDef *) DMA1_Channel5_BASE)
#define DMA1_Channel6 ((DMA_Channel_TypeDef *) DMA1_Channel6_BASE)
#define DMA1_Channel7 ((DMA_Channel_TypeDef *) DMA1_Channel7_BASE)
#define DMA2_Channel1 ((DMA_Channel_TypeDef *) DMA2_Channel1_BASE)
#define DMA2_Channel2 ((DMA_Channel_TypeDef *) DMA2_Channel2_BASE)
#define DMA2_Channel3 ((DMA_Channel_TypeDef *) DMA2_Channel3_BASE)
#define DMA2_Channel4 ((DMA_Channel_TypeDef *) DMA2_Channel4_BASE)
#define DMA2_Channel5 ((DMA_Channel_TypeDef *) DMA2_Channel5_BASE)DMA_InitTypeDef
/***stm32f10x_dma.h***/
typedef struct
{
uint32_t DMA_PeripheralBaseAddr;
uint32_t DMA_MemoryBaseAddr;
uint32_t DMA_DIR;
uint32_t DMA_BufferSize;
uint32_t DMA_PeripheralInc;
uint32_t DMA_MemoryInc;
uint32_t DMA_PeripheralDataSize;
uint32_t DMA_MemoryDataSize;
uint32_t DMA_Mode;
uint32_t DMA_Priority;
uint32_t DMA_M2M;
}DMA_InitTypeDef;
#define DMA_DIR_PeripheralDST ((uint32_t)0x00000010)
#define DMA_DIR_PeripheralSRC ((uint32_t)0x00000000)
#define IS_DMA_DIR(DIR) (((DIR) == DMA_DIR_PeripheralDST) || \
((DIR) == DMA_DIR_PeripheralSRC))
#define DMA_PeripheralInc_Enable ((uint32_t)0x00000040)
#define DMA_PeripheralInc_Disable ((uint32_t)0x00000000)
#define IS_DMA_PERIPHERAL_INC_STATE(STATE) (((STATE) == DMA_PeripheralInc_Enable) || \
((STATE) == DMA_PeripheralInc_Disable))
#define DMA_MemoryInc_Enable ((uint32_t)0x00000080)
#define DMA_MemoryInc_Disable ((uint32_t)0x00000000)
#define IS_DMA_MEMORY_INC_STATE(STATE) (((STATE) == DMA_MemoryInc_Enable) || \
((STATE) == DMA_MemoryInc_Disable))
#define DMA_PeripheralDataSize_Byte ((uint32_t)0x00000000)
#define DMA_PeripheralDataSize_HalfWord ((uint32_t)0x00000100)
#define DMA_PeripheralDataSize_Word ((uint32_t)0x00000200)
#define IS_DMA_PERIPHERAL_DATA_SIZE(SIZE) (((SIZE) == DMA_PeripheralDataSize_Byte) || \
((SIZE) == DMA_PeripheralDataSize_HalfWord) || \
((SIZE) == DMA_PeripheralDataSize_Word))
#define DMA_MemoryDataSize_Byte ((uint32_t)0x00000000)
#define DMA_MemoryDataSize_HalfWord ((uint32_t)0x00000400)
#define DMA_MemoryDataSize_Word ((uint32_t)0x00000800)
#define IS_DMA_MEMORY_DATA_SIZE(SIZE) (((SIZE) == DMA_MemoryDataSize_Byte) || \
((SIZE) == DMA_MemoryDataSize_HalfWord) || \
((SIZE) == DMA_MemoryDataSize_Word))
#define DMA_Mode_Circular ((uint32_t)0x00000020)
#define DMA_Mode_Normal ((uint32_t)0x00000000)
#define IS_DMA_MODE(MODE) (((MODE) == DMA_Mode_Circular) || ((MODE) == DMA_Mode_Normal))
#define DMA_Priority_VeryHigh ((uint32_t)0x00003000)
#define DMA_Priority_High ((uint32_t)0x00002000)
#define DMA_Priority_Medium ((uint32_t)0x00001000)
#define DMA_Priority_Low ((uint32_t)0x00000000)
#define IS_DMA_PRIORITY(PRIORITY) (((PRIORITY) == DMA_Priority_VeryHigh) || \
((PRIORITY) == DMA_Priority_High) || \
((PRIORITY) == DMA_Priority_Medium) || \
((PRIORITY) == DMA_Priority_Low))
#define DMA_M2M_Enable ((uint32_t)0x00004000)
#define DMA_M2M_Disable ((uint32_t)0x00000000)
#define IS_DMA_M2M_STATE(STATE) (((STATE) == DMA_M2M_Enable) || ((STATE) == DMA_M2M_Disable))3.2 函数
DMA_Init（）
void DMA_Init(DMA_Channel_TypeDef* DMAy_Channelx, DMA_InitTypeDef* DMA_InitStruct)
{
uint32_t tmpreg = 0;
/* Check the parameters */
assert_param(IS_DMA_ALL_PERIPH(DMAy_Channelx));
assert_param(IS_DMA_DIR(DMA_InitStruct->DMA_DIR));
assert_param(IS_DMA_BUFFER_SIZE(DMA_InitStruct->DMA_BufferSize));
assert_param(IS_DMA_PERIPHERAL_INC_STATE(DMA_InitStruct->DMA_PeripheralInc));
assert_param(IS_DMA_MEMORY_INC_STATE(DMA_InitStruct->DMA_MemoryInc));
assert_param(IS_DMA_PERIPHERAL_DATA_SIZE(DMA_InitStruct->DMA_PeripheralDataSize));
assert_param(IS_DMA_MEMORY_DATA_SIZE(DMA_InitStruct->DMA_MemoryDataSize));
assert_param(IS_DMA_MODE(DMA_InitStruct->DMA_Mode));
assert_param(IS_DMA_PRIORITY(DMA_InitStruct->DMA_Priority));
assert_param(IS_DMA_M2M_STATE(DMA_InitStruct->DMA_M2M));
/*--------------------------- DMAy Channelx CCR Configuration -----------------*/
/* Get the DMAy_Channelx CCR value */
tmpreg = DMAy_Channelx->CCR;
/* Clear MEM2MEM, PL, MSIZE, PSIZE, MINC, PINC, CIRC and DIR bits */
tmpreg &= CCR_CLEAR_Mask;
/* Configure DMAy Channelx: data transfer, data size, priority level and mode */
/* Set DIR bit according to DMA_DIR value */
/* Set CIRC bit according to DMA_Mode value */
/* Set PINC bit according to DMA_PeripheralInc value */
/* Set MINC bit according to DMA_MemoryInc value */
/* Set PSIZE bits according to DMA_PeripheralDataSize value */
/* Set MSIZE bits according to DMA_MemoryDataSize value */
/* Set PL bits according to DMA_Priority value */
/* Set the MEM2MEM bit according to DMA_M2M value */
tmpreg |= DMA_InitStruct->DMA_DIR | DMA_InitStruct->DMA_Mode |
DMA_InitStruct->DMA_PeripheralInc | DMA_InitStruct->DMA_MemoryInc |
DMA_InitStruct->DMA_PeripheralDataSize | DMA_InitStruct->DMA_MemoryDataSize |
DMA_InitStruct->DMA_Priority | DMA_InitStruct->DMA_M2M;
/* Write to DMAy Channelx CCR */
DMAy_Channelx->CCR = tmpreg;
/*--------------------------- DMAy Channelx CNDTR Configuration ---------------*/
/* Write to DMAy Channelx CNDTR */
DMAy_Channelx->CNDTR = DMA_InitStruct->DMA_BufferSize;
/*--------------------------- DMAy Channelx CPAR Configuration ----------------*/
/* Write to DMAy Channelx CPAR */
DMAy_Channelx->CPAR = DMA_InitStruct->DMA_PeripheralBaseAddr;
/*--------------------------- DMAy Channelx CMAR Configuration ----------------*/
/* Write to DMAy Channelx CMAR */
DMAy_Channelx->CMAR = DMA_InitStruct->DMA_MemoryBaseAddr;
}DMA_StructInit（）
void DMA_StructInit(DMA_InitTypeDef* DMA_InitStruct)
{
/*-------------- Reset DMA init structure parameters values ------------------*/
/*CPAR通道外设地址寄存器*/
DMA_InitStruct->DMA_PeripheralBaseAddr = 0;
/*CMAR通道存储器地址寄存器*/
DMA_InitStruct->DMA_MemoryBaseAddr = 0;
/*CNDTR通道传输数据量寄存器*/
DMA_InitStruct->DMA_BufferSize = 0;
DMA_InitStruct->DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStruct->DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStruct->DMA_MemoryInc = DMA_MemoryInc_Disable;
DMA_InitStruct->DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStruct->DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStruct->DMA_Mode = DMA_Mode_Normal;
DMA_InitStruct->DMA_Priority = DMA_Priority_Low;
DMA_InitStruct->DMA_M2M = DMA_M2M_Disable;
}DMA_Cmd（）
/***可能所有外设的使能都是peripheral_cmd()***/
void DMA_Cmd(DMA_Channel_TypeDef* DMAy_Channelx, FunctionalState NewState)
{
/* Check the parameters */
assert_param(IS_DMA_ALL_PERIPH(DMAy_Channelx));
assert_param(IS_FUNCTIONAL_STATE(NewState));
if (NewState != DISABLE)
{
/* Enable the selected DMAy Channelx */
DMAy_Channelx->CCR |= DMA_CCR1_EN;
}
else
{
/* Disable the selected DMAy Channelx */
DMAy_Channelx->CCR &= (uint16_t)(~DMA_CCR1_EN);
}
}DMA_ITConfig()
/***CCR中三个中断函数使能配置,TEIE、HTIE、TCIE;***/
#define DMA_IT_TC ((uint32_t)0x00000002)
#define DMA_IT_HT ((uint32_t)0x00000004)
#define DMA_IT_TE ((uint32_t)0x00000008)
#define IS_DMA_CONFIG_IT(IT) ((((IT) & 0xFFFFFFF1) == 0x00) && ((IT) != 0x00))
void DMA_ITConfig(DMA_Channel_TypeDef* DMAy_Channelx, uint32_t DMA_IT, FunctionalState NewState)
{
/* Check the parameters */
assert_param(IS_DMA_ALL_PERIPH(DMAy_Channelx));
assert_param(IS_DMA_CONFIG_IT(DMA_IT));
assert_param(IS_FUNCTIONAL_STATE(NewState));
if (NewState != DISABLE)
{
/* Enable the selected DMA interrupts */
DMAy_Channelx->CCR |= DMA_IT;
}
else
{
/* Disable the selected DMA interrupts */
DMAy_Channelx->CCR &= ~DMA_IT;
}
}DMA_SetCurrDataCounter（）
void DMA_SetCurrDataCounter(DMA_Channel_TypeDef* DMAy_Channelx, uint16_t DataNumber)
{
/* Check the parameters */
assert_param(IS_DMA_ALL_PERIPH(DMAy_Channelx));
/*--------------------------- DMAy Channelx CNDTR Configuration ---------------*/
/* Write to DMAy Channelx CNDTR */
DMAy_Channelx->CNDTR = DataNumber;
}DMA_GetCurrDataCounter（）
uint16_t DMA_GetCurrDataCounter(DMA_Channel_TypeDef* DMAy_Channelx)
{
/* Check the parameters */
assert_param(IS_DMA_ALL_PERIPH(DMAy_Channelx));
/* Return the number of remaining data units for DMAy Channelx */
return ((uint16_t)(DMAy_Channelx->CNDTR));
}DMA_GetFlagStatus（）
/***ISR寄存器对应bit读取，和后面的DMA_GetITStatus()函数完全一样；***/
#define IS_DMA_GET_FLAG(FLAG) (((FLAG) == DMA1_FLAG_GL1) || ((FLAG) == DMA1_FLAG_TC1) || ((FLAG) == DMA1_FLAG_HT1) || ((FLAG) == DMA1_FLAG_TE1) || \
((FLAG) == DMA1_FLAG_GL2) || ((FLAG) == DMA1_FLAG_TC2) || ((FLAG) == DMA1_FLAG_HT2) || ((FLAG) == DMA1_FLAG_TE2) || \
((FLAG) == DMA1_FLAG_GL3) || ((FLAG) == DMA1_FLAG_TC3) || ((FLAG) == DMA1_FLAG_HT3) || ((FLAG) == DMA1_FLAG_TE3) || \
((FLAG) == DMA1_FLAG_GL4) || ((FLAG) == DMA1_FLAG_TC4) || ((FLAG) == DMA1_FLAG_HT4) || ((FLAG) == DMA1_FLAG_TE4) || \
((FLAG) == DMA1_FLAG_GL5) || ((FLAG) == DMA1_FLAG_TC5) || ((FLAG) == DMA1_FLAG_HT5) || ((FLAG) == DMA1_FLAG_TE5) || \
((FLAG) == DMA1_FLAG_GL6) || ((FLAG) == DMA1_FLAG_TC6) || ((FLAG) == DMA1_FLAG_HT6) || ((FLAG) == DMA1_FLAG_TE6) || \
((FLAG) == DMA1_FLAG_GL7) || ((FLAG) == DMA1_FLAG_TC7) || ((FLAG) == DMA1_FLAG_HT7) || ((FLAG) == DMA1_FLAG_TE7) || \
((FLAG) == DMA2_FLAG_GL1) || ((FLAG) == DMA2_FLAG_TC1) || ((FLAG) == DMA2_FLAG_HT1) || ((FLAG) == DMA2_FLAG_TE1) || \
((FLAG) == DMA2_FLAG_GL2) || ((FLAG) == DMA2_FLAG_TC2) || ((FLAG) == DMA2_FLAG_HT2) || ((FLAG) == DMA2_FLAG_TE2) || \
((FLAG) == DMA2_FLAG_GL3) || ((FLAG) == DMA2_FLAG_TC3) || ((FLAG) == DMA2_FLAG_HT3) || ((FLAG) == DMA2_FLAG_TE3) || \
((FLAG) == DMA2_FLAG_GL4) || ((FLAG) == DMA2_FLAG_TC4) || ((FLAG) == DMA2_FLAG_HT4) || ((FLAG) == DMA2_FLAG_TE4) || \
((FLAG) == DMA2_FLAG_GL5) || ((FLAG) == DMA2_FLAG_TC5) || ((FLAG) == DMA2_FLAG_HT5) || ((FLAG) == DMA2_FLAG_TE5))
FlagStatus DMA_GetFlagStatus(uint32_t DMAy_FLAG)
{
FlagStatus bitstatus = RESET;
uint32_t tmpreg = 0;
/* Check the parameters */
assert_param(IS_DMA_GET_FLAG(DMAy_FLAG));
/* Calculate the used DMAy */
if ((DMAy_FLAG & FLAG_Mask) != (uint32_t)RESET)
{
/* Get DMA2 ISR register value */
tmpreg = DMA2->ISR ;
}
else
{
/* Get DMA1 ISR register value */
tmpreg = DMA1->ISR ;
}
/* Check the status of the specified DMAy flag */
if ((tmpreg & DMAy_FLAG) != (uint32_t)RESET)
{
/* DMAy_FLAG is set */
bitstatus = SET;
}
else
{
/* DMAy_FLAG is reset */
bitstatus = RESET;
}
/* Return the DMAy_FLAG status */
return bitstatus;
}DMA_ClearFlag（）
/***IFCR对应位配置，用来清除ISR中对应位；
***和后面的DMA_ClearITPendingBit（）是逻辑相同的函数；***/
#define IS_DMA_CLEAR_FLAG(FLAG) (((((FLAG) & 0xF0000000) == 0x00) || (((FLAG) & 0xEFF00000) == 0x00)) && ((FLAG) != 0x00))
void DMA_ClearFlag(uint32_t DMAy_FLAG)
{
/* Check the parameters */
assert_param(IS_DMA_CLEAR_FLAG(DMAy_FLAG));
/* Calculate the used DMAy */
if ((DMAy_FLAG & FLAG_Mask) != (uint32_t)RESET)
{
/* Clear the selected DMAy flags */
DMA2->IFCR = DMAy_FLAG;
}
else
{
/* Clear the selected DMAy flags */
DMA1->IFCR = DMAy_FLAG;
}
}DMA_GetITStatus（）
/*这函数和前面的DMA_GetFlagStatus()完全一样，就是为了对齐凑数的；*/
ITStatus DMA_GetITStatus(uint32_t DMAy_IT)
{
ITStatus bitstatus = RESET;
uint32_t tmpreg = 0;
/* Check the parameters */
assert_param(IS_DMA_GET_IT(DMAy_IT));
/* Calculate the used DMA */
if ((DMAy_IT & FLAG_Mask) != (uint32_t)RESET)
{
/* Get DMA2 ISR register value */
tmpreg = DMA2->ISR;
}
else
{
/* Get DMA1 ISR register value */
tmpreg = DMA1->ISR;
}
/* Check the status of the specified DMAy interrupt */
if ((tmpreg & DMAy_IT) != (uint32_t)RESET)
{
/* DMAy_IT is set */
bitstatus = SET;
}
else
{
/* DMAy_IT is reset */
bitstatus = RESET;
}
/* Return the DMA_IT status */
return bitstatus;
}DMA_ClearITPendingBit（）
/*清除IFCR中的中断flag位，和前面的DMA_ClearFlag()代码相同，这个函数也是凑数的；*/
#define IS_DMA_CLEAR_IT(IT) (((((IT) & 0xF0000000) == 0x00) || (((IT) & 0xEFF00000) == 0x00)) && ((IT) != 0x00))
void DMA_ClearITPendingBit(uint32_t DMAy_IT)
{
/* Check the parameters */
assert_param(IS_DMA_CLEAR_IT(DMAy_IT));
/* Calculate the used DMAy */
if ((DMAy_IT & FLAG_Mask) != (uint32_t)RESET)
{
/* Clear the selected DMAy interrupt pending bits */
DMA2->IFCR = DMAy_IT;
}
else
{
/* Clear the selected DMAy interrupt pending bits */
DMA1->IFCR = DMAy_IT;
}
}4 使用函数
dma.c
#include "dma.h"
#include "usart.h"
u8 dma_to_usart1_buf[dma2usart_buf_size];
u8 usart1_to_dma_buf[buf_size];
u8 mem2mem_src[buf_size]={0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
u8 mem2mem_des[buf_size]={0};
void dma2usart_buf_init(void)
{
int i=0;
u8 j=0;
for(i=0;i<dma2usart_buf_size;i++){
dma_to_usart1_buf[i]=j;
j++;
}
}
void dma_to_usart1_init(void)
{
dma2usart_buf_init();
DMA_InitTypeDef DMA_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
DMA_InitStructure.DMA_PeripheralBaseAddr = (USART1_BASE+0x04);
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)dma_to_usart1_buf;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = dma2usart_buf_size;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel4, &DMA_InitStructure);
DMA_Cmd (DMA1_Channel4,ENABLE);
USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);
}
void usart1_to_dma_init(void)
{
DMA_InitTypeDef DMA_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
DMA_InitStructure.DMA_PeripheralBaseAddr = (USART1_BASE+0x04);
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)usart1_to_dma_buf;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = buf_size;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal ;
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel5, &DMA_InitStructure);
DMA_Cmd (DMA1_Channel5,ENABLE);
USART_DMACmd(USART1, USART_DMAReq_Rx, ENABLE);
while( !DMA_GetFlagStatus(DMA1_FLAG_TC5) )
;
DMA_ClearFlag(DMA1_FLAG_TC5);
int i=0;
for(i=0;i<buf_size;i++)
printf("%x",usart1_to_dma_buf[i]);
}
void dma_to_dma_init(void)
{
DMA_InitTypeDef DMA_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)mem2mem_src;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)mem2mem_des;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = buf_size;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable;
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_Normal ;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Enable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
DMA_Cmd(DMA1_Channel1,ENABLE);
while( !DMA_GetFlagStatus(DMA1_FLAG_TC1) )
;
DMA_ClearFlag(DMA1_FLAG_TC1);
int i=0;
for(i=0;i<buf_size;i++)
printf("%x",mem2mem_des[i]);
}
