stm32 hal库uart发送函数
时间: 2023-05-25 18:03:07 浏览: 144
以下是STM32 HAL库的UART发送函数,该函数通过串行外设接口(UART)将数据发送到目标设备或主机:
```c
HAL_StatusTypeDef HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)
```
参数解释:
- `huart`: 一个指向UART_HandleTypeDef结构体的指针,该结构体包含了HAL库中使用的所有UART外设的相关信息,例如UART接口号、波特率、数据位数等等;
- `pData`: 要发送的数据缓冲区的指针;
- `Size`: 要发送的数据长度;
- `Timeout`: 延迟时间(单位:毫秒),如果发送操作不能在此时间之间完成,函数将返回HAL_TIMEOUT错误。
例如,以下代码段可以将字符串发送到 UART1 并等待操作完成:
```c
char *str = "Hello World!";
HAL_UART_Transmit(&huart1, (uint8_t *)str, strlen(str), HAL_MAX_DELAY);
```
需要注意的是,由于HAL_UART_Transmit函数是阻塞的,因此会一直等待串口发送完成(或超时)。如果需要在发送数据期间执行其他任务,则需要使用DMA或中断等方式进行异步发送和接收。
相关问题
stm32 hal库uart中断形式发送函数
这里给出一个基于STM32 HAL库的UART中断发送函数示例:
```c
#define UART_TX_BUF_SIZE 128
static uint16_t uart_tx_head = 0;
static uint16_t uart_tx_tail = 0;
static uint8_t uart_tx_buf[UART_TX_BUF_SIZE];
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart) {
if (huart->Instance == USART1) {
if (uart_tx_head != uart_tx_tail) {
// 继续发送下一批数据
uint8_t data = uart_tx_buf[uart_tx_tail++];
uart_tx_tail %= UART_TX_BUF_SIZE;
HAL_UART_Transmit_IT(huart, &data, 1);
}
}
}
void uart_send_async(UART_HandleTypeDef *huart, const uint8_t *data, uint16_t len) {
// 将数据拷贝到发送缓冲区
for (uint16_t i = 0; i < len; i++) {
uart_tx_buf[uart_tx_head++] = data[i];
uart_tx_head %= UART_TX_BUF_SIZE;
}
// 如果当前没有在发送数据,则启动发送
if (!huart->gState) {
uint8_t data = uart_tx_buf[uart_tx_tail++];
uart_tx_tail %= UART_TX_BUF_SIZE;
HAL_UART_Transmit_IT(huart, &data, 1);
}
}
```
这个函数支持将数据异步发送出去,发送时不会阻塞主程序。在发送数据时,先将数据拷贝到发送缓冲区中,然后检查UART是否已经在发送数据。如果没有在发送,则启动发送;如果正在发送,则等待发送完成后继续发送。
当UART传输完成时,会触发`HAL_UART_TxCpltCallback`回调函数。此时检查一下缓冲区是否还有数据需要发送,如果有,则继续发送下一批数据。如果没有,说明已经全部发送完成,结束发送。
STM32F407 HAL库uart发送函数
以下是STM32F407 HAL库uart发送函数的示例代码:
```
/**
* @brief Sends an amount of data through the UARTx peripheral.
* @param huart: UART handle.
* @param pData: Pointer to data buffer.
* @param Size: Amount of data to be sent.
* @retval HAL status.
*/
HAL_StatusTypeDef HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)
{
uint16_t* tmp;
uint16_t uhMask;
uint32_t tickstart = 0U;
/* Check that a Tx process is not already ongoing */
if(huart->gState == HAL_UART_STATE_READY)
{
/* Compile time check if possible */
#if (USE_HAL_UART_REGISTER_CALLBACKS == 1)
/* Call registered Tx complete callback */
huart->TxCpltCallback(huart);
#else
/* Tx transfer start */
huart->gState = HAL_UART_STATE_BUSY_TX;
#endif /* USE_HAL_UART_REGISTER_CALLBACKS */
huart->ErrorCode = HAL_UART_ERROR_NONE;
if(huart->Init.WordLength == UART_WORDLENGTH_9B)
{
if(huart->Init.Parity == UART_PARITY_NONE)
{
tmp = (uint16_t*) pData;
uhMask = 0x01FFU; /* 9 bits */
}
else
{
tmp = (uint16_t*) pData;
uhMask = 0x00FFU; /* 8 bits + parity */
}
}
else
{
tmp = (uint16_t*) pData;
uhMask = 0x007FU; /* 7 bits */
}
huart->TxXferCount = Size;
/* To avoid building warning message */
/* (__GNUC__ compiler: cast between incompatible function types) */
/* cast pData to uint16_t* in case of 9bits or 8bits + parity format */
huart->pTxBuffPtr = (uint8_t*)(tmp);
huart->TxXferSize = Size;
/* Process Locked */
__HAL_LOCK(huart);
/* Enable the UART Transmit data register empty Interrupt */
__HAL_UART_ENABLE_IT(huart, UART_IT_TXE);
tickstart = HAL_GetTick();
while(huart->TxXferCount > 0U)
{
if((Timeout == 0U) || ((HAL_GetTick()-tickstart) > Timeout))
{
huart->gState = HAL_UART_STATE_TIMEOUT;
/* Process Unlocked */
__HAL_UNLOCK(huart);
return HAL_TIMEOUT;
}
}
/* At end of Tx process, restore huart->pTxBuffPtr and huart->TxXferSize
(could have been changed during Tx process) */
huart->pTxBuffPtr = pData;
huart->TxXferSize = Size;
/* Disable the UART Transmit data register empty Interrupt */
__HAL_UART_DISABLE_IT(huart, UART_IT_TXE);
/* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
__HAL_UART_DISABLE_IT(huart, UART_IT_ERR);
/* Process Unlocked */
__HAL_UNLOCK(huart);
/* Call Tx complete callback */
#if (USE_HAL_UART_REGISTER_CALLBACKS == 1)
/* Call registered Tx complete callback */
huart->TxCpltCallback(huart);
#else
/* Call legacy weak Tx complete callback */
HAL_UART_TxCpltCallback(huart);
#endif /* USE_HAL_UART_REGISTER_CALLBACKS */
return HAL_OK;
}
else
{
return HAL_BUSY;
}
}
```
此函数将发送数据缓冲区指针,要发送的数据大小和超时作为参数。在调用此函数之前,必须先初始化UART外设和使用HAL_UART_MspInit()函数配置外设时钟、GPIO等引脚。在发送数据之后,可以使用回调函数处理传输完成事件,或者使用轮询检查状态。在数据传输期间,数据将通过UART外设发送,并在传输完成后通过回调函数或轮询调用进行通知。如果传输过程中超时,函数将返回HAL_TIMEOUT状态。