STM8开发记录二：UART RX空闲中断和DMA操作
一、用STM8L的时候，没能在同时读取Rx中断和IDLE中断标志，最后用DMA取数据，见 （三、DMA实现数据拷贝）：
1.1 uart配置
void UsartConfig(void)
{
// USART_DeInit(USART1);
/* Enable USART clock */
CLK_PeripheralClockConfig(CLK_Peripheral_USART1, ENABLE);
/* USART pin remap */
SYSCFG_REMAPPinConfig(REMAP_Pin_USART1TxRxPortA, ENABLE);
/* Configure USART Tx as alternate function push-pull (software pull up)*/
GPIO_ExternalPullUpConfig(USART1_Tx_PORT, USART1_Tx_Pin, ENABLE);
/* Configure USART Rx as alternate function push-pull (software pull up)*/
GPIO_ExternalPullUpConfig(USART1_Rx_PORT, USART1_Rx_Pin, ENABLE);
/* USART configuration */
USART_Init(USART1, BAUDRATE, USART_WordLength_8b, USART_StopBits_1,
USART_Parity_No, USART_Mode_Rx_and_TX);
/* Enable the USART Receive interrupt: this interrupt is generated when the USART*/
USART_ITConfig(USART1 , USART_IT_RXNE, ENABLE);
USART_ITConfig(USART1 , USART_IT_IDLE , ENABLE); //空闲中断
//配置ITC 中断管理
ITC_SetSoftwarePriority(USART1_RX_IRQn, ITC_PriorityLevel_3);
//start UART
USART_Cmd(USART1 , ENABLE); //打开串口
//解决第一个数据发送失败的问题
USART_ClearFlag(USART3 , USART_FLAG_TC);
// USART_ClearFlag(USART3 , USART_FLAG_IDLE);
}
1.2 中断处理， 不能判断IDLE中断：如发送 AA01数据后，不能进入IDLE中断。
但是只开IDLE中断，发送完毕会进入IDLE中断。
/* Enable the USART Receive interrupt: this interrupt is generated when the USART*/
//USART_ITConfig(USART1 , USART_IT_RXNE, ENABLE);
USART_ITConfig(USART1 , USART_IT_IDLE , ENABLE); //空闲中断
INTERRUPT_HANDLER(USART1_RX_TIM5_CC_IRQHandler, 28)
{
/* In order to detect unexpected events during development,
it is recommended to set a breakpoint on the following instruction.
*/
static U8 BytesPos = 0;
static U8 MessagePos = 0;
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //RX interrupt
{
UartApiVar.RXBuffer[MessagePos][BytesPos] = USART_ReceiveData8(USART1);
printflog("MessagePos = %d, BytesPos = %d\n\r", MessagePos, BytesPos);
printflog("data_0 = %d\n\r", UartApiVar.RXBuffer[MessagePos][BytesPos]);
BytesPos++;
}
else if(USART_GetITStatus(USART1, USART_IT_IDLE) != RESET) //IDLE interrupt
{
USART1->SR;//先读SR
USART1->DR;//再读DR
printflog("MessagePos = %d, BytesPos = %d\n\r", MessagePos, BytesPos);
printflog("data_1 = %d\n\r", UartApiVar.RXBuffer[MessagePos][0]);
if((BytesPos < COMM_IF_UART_RX_BUFFER_LENGTH) &&
(UartApiVar.RXBuffer[MessagePos][0] == 0xAA))
{
if(MessagePos < COMM_IF_UART_RX_MSG_NUM)
{
MessagePos++;
}
else
{
MessagePos = 0;
}
}
BytesPos = 0;
}
}
二、用STM32的时候，可以同时判断Rx中断和IDLE中断：
2.1 uart配置：
void USART3Conf(u32 baudRate, u32 nvicPre, u32 nvicSub)
{
USART_InitTypeDef USART_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE); //使能USART1
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); //GPIOA时钟
//USART3_TX GPIOB.10
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; //PB10
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIOA.10
//USART3_RX GPIOB.11初始化
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;//PB11
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//浮空输入
GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIOA.10
// //Usart3 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=nvicPre ;//抢占优先级3
NVIC_InitStructure.NVIC_IRQChannelSubPriority = nvicSub; //子优先级2
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器
//USART3 Configure
USART_InitStructure.USART_BaudRate = baudRate;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
//USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART3 , &USART_InitStructure);
//USART3_INT Configure
USART_ITConfig(USART3 , USART_IT_RXNE, ENABLE);
USART_ITConfig(USART3 , USART_IT_IDLE , ENABLE); //空闲中断
USART_Cmd(USART3 , ENABLE);//打开串口
USART_ClearFlag(USART3 , USART_FLAG_TC);//解决第一个数据发送失败的问题
}
2.2中断处理：
void USART3_IRQHandler(void)
{
static u8 i = 0;
if(USART_GetITStatus(USART3, USART_IT_RXNE) != RESET)
{
UsartBuf[i] = (u8)USART_ReceiveData(USART3);
i++;
/* deliver rx byte */
}
else if(USART_GetITStatus(USART3, USART_IT_IDLE) != RESET)
{
USART3->SR;//先读SR
USART3->DR;//再读DR
if(UsartBuf[i -1] == 0x0A)
{
UsartBuf[UART_DATA_LEN -2] = i;
UsartBuf[UART_DATA_LEN -1] = UART_DATA_END_CODE;
}
i = 0;
}
if(USART_GetITStatus(USART3, USART_IT_TXE) != RESET)
{
}
}三、鉴于STM8L没有能让RX和IDLE中断标志同时置位，故采用DMA实现数据拷贝。
3.1DMA配置：
/**********************************************************************/
//Description: DmaConfig()
//Parameters: //0x5231, 为UART数据寄存器地址：USART1_BASE = 0x5230
//Return:
//Date: quanwu.xu
/**********************************************************************/
void DmaConfig(void)
{
CLK_PeripheralClockConfig(CLK_Peripheral_DMA1, ENABLE);//打开时钟，很重要
/* Deinitialize DMA channels */
DMA_GlobalDeInit();
DMA_DeInit(DMA1_Channel1);
DMA_DeInit(DMA1_Channel2);
/* DMA channel Rx of USART Configuration */ //该函数主要要配置好接受的数组，以及USART的数据寄存器地址，数组大小，以及DMA模式
DMA_Init(DMA1_Channel2, (uint16_t)UartApiVar.RxBuffer, UART_DR_ADDRESS,
COMM_IF_UART_RX_BUFFER_LENGTH, DMA_DIR_PeripheralToMemory, DMA_Mode_Normal,
DMA_MemoryIncMode_Inc, DMA_Priority_High, DMA_MemoryDataSize_Byte);
/* DMA channel Tx of USART Configuration */ //该函数主要配置发送数组，以及USART的数据寄存器地址，数组大小，以及DMA模式
DMA_Init(DMA1_Channel1, (uint16_t)UartApiVar.TxBuffer, UART_DR_ADDRESS,
COMM_IF_UART_TX_BUFFER_LENGTH, DMA_DIR_MemoryToPeripheral, DMA_Mode_Normal,
DMA_MemoryIncMode_Inc, DMA_Priority_Low, DMA_MemoryDataSize_Byte);
/* Enable the USART Tx/Rx DMA requests */
USART_DMACmd(USART1, USART_DMAReq_TX, ENABLE);
USART_DMACmd(USART1, USART_DMAReq_RX, ENABLE);
/* Global DMA Enable */
DMA_GlobalCmd(ENABLE);
/* Enable the USART Tx DMA channel */
DMA_Cmd(DMA1_Channel1, ENABLE);
/* Enable the USART Rx DMA channel */
DMA_Cmd(DMA1_Channel2, ENABLE);
}
3.2UART配置，只使能IDLE中断
/**********************************************************************/
//Description: UsartConfig()
//Parameters:
//Return:
//Date: quanwu.xu
/**********************************************************************/
void UsartConfig(void)
{
USART_DeInit(USART1);
/* Enable USART clock */
CLK_PeripheralClockConfig(CLK_Peripheral_USART1, ENABLE);
/* USART pin remap */
SYSCFG_REMAPPinConfig(REMAP_Pin_USART1TxRxPortA, ENABLE);
/* Configure USART Tx as alternate function push-pull (software pull up)*/
GPIO_ExternalPullUpConfig(USART1_Tx_PORT, USART1_Tx_Pin, ENABLE);
/* Configure USART Rx as alternate function push-pull (software pull up)*/
GPIO_ExternalPullUpConfig(USART1_Rx_PORT, USART1_Rx_Pin, ENABLE);
/* USART configuration */
USART_Init(USART1, BAUDRATE, USART_WordLength_8b, USART_StopBits_1,
USART_Parity_No, USART_Mode_Rx_and_TX);
/* Enable the USART Receive interrupt: this interrupt is generated when the USART*/
//USART_ITConfig(USART1 , USART_IT_RXNE, ENABLE);
USART_ITConfig(USART1 , USART_IT_IDLE , ENABLE); //空闲中断
//配置ITC 中断管理
ITC_SetSoftwarePriority(USART1_RX_IRQn, ITC_PriorityLevel_3);
//start UART
USART_Cmd(USART1 , ENABLE); //打开串口
//解决第一个数据发送失败的问题
USART_ClearFlag(USART3 , USART_FLAG_TC);
}
3.3 UART IDLE中断处理函数
extern void* Memcpy(void* pDest, void* pSrc, U8 Len);
INTERRUPT_HANDLER(USART1_RX_TIM5_CC_IRQHandler, 28)
{
/* In order to detect unexpected events during development,
it is recommended to set a breakpoint on the following instruction.
*/
static U8 MessagePos = 0;
U8 DataLen = 0;
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //RX interrupt
{
}
else if(USART_GetITStatus(USART1, USART_IT_IDLE) != RESET) //IDLE interrupt
{
USART1->SR;//先读SR
USART1->DR;//再读DR
DataLen = COMM_IF_UART_RX_BUFFER_LENGTH -
DMA_GetCurrDataCounter(DMA1_Channel2);
if(DataLen < COMM_IF_UART_RX_BUFFER_LENGTH)
{
printflog("RxBuffer[0]=%x\n\r", UartApiVar.RxBuffer[0]);
Memcpy((void*)&UartApiVar.RxMessage[MessagePos],
(void*)&UartApiVar.RxBuffer, DataLen);
if(++MessagePos == COMM_IF_UART_RX_MSG_NUM)
{
MessagePos = 0;
}
SystemApiVar.UartWakeupFlag = 1;
}
DMA_Cmd(DMA1_Channel2, DISABLE);
DMA_SetCurrDataCounter(DMA1_Channel2, COMM_IF_UART_RX_BUFFER_LENGTH);
DMA_Cmd(DMA1_Channel2, ENABLE);
}
}
3.4 其他相关定义和函数
/*****************************************************************************/
//uart.h
#define UART_DR_ADDRESS ((uint16_t)0x5231) //UART寄存器地址
/*! UART RX Buffer size */
#ifndef COMM_IF_UART_RX_BUFFER
#define COMM_IF_UART_RX_MSG_NUM 4
#define COMM_IF_UART_RX_BUFFER_LENGTH 16u
#endif
/*! UART TX Buffer size */
#ifndef COMM_IF_UART_TX_BUFFER
#define COMM_IF_UART_TX_MSG_NUM 4
#define COMM_IF_UART_TX_BUFFER_LENGTH 16u
#endif
typedef struct _UartApi
{
U8 RxBuffer[COMM_IF_UART_RX_BUFFER_LENGTH];
U8 RxMessage[COMM_IF_UART_RX_MSG_NUM][COMM_IF_UART_RX_BUFFER_LENGTH];
U8 TxBuffer[COMM_IF_UART_RX_BUFFER_LENGTH];
U8 TxMessage[COMM_IF_UART_TX_MSG_NUM][COMM_IF_UART_TX_BUFFER_LENGTH];
}UartApi;
/*****************************************************************************/
//定义全局变量
SystemApi SystemApiVar;
/*****************************************************************************/
//Mempcy函数原型
/**********************************************************************/
//Description: Memcpy()
//Parameters:
//Return:
//Date: quanwu.xu
/**********************************************************************/
void* Memcpy(void* pDest, const void* pSrc, U8 Len)
{
char* Des = (char*)pDest;
char* Src = (char*)pSrc;
if (Des == NULL ||Src == NULL)
{
return NULL;
}
while(Len--)
{
*Des++ = *Src++; // *(char *)pDest++ = *(char *)pSrc++ , IAR编译异常
}
return pDest;
}