Exemplo n.º 1
0
/**
 * @brief   RX DMA common service routine.
 *
 * @param[in] uartp     pointer to the @p UARTDriver object
 * @param[in] flags     pre-shifted content of the ISR register
 */
static void uart_lld_serve_rx_end_irq(UARTDriver *uartp, uint32_t flags) {

  /* DMA errors handling.*/
#if defined(STM32_UART_DMA_ERROR_HOOK)
  if ((flags & (STM32_DMA_ISR_TEIF | STM32_DMA_ISR_DMEIF)) != 0) {
    STM32_UART_DMA_ERROR_HOOK(uartp);
  }
#else
  (void)flags;
#endif

  if (uartp->rxstate == UART_RX_IDLE) {
    /* Receiver in idle state, a callback is generated, if enabled, for each
       received character and then the driver stays in the same state.*/
    if (uartp->config->rxchar_cb != NULL)
      uartp->config->rxchar_cb(uartp, uartp->rxbuf);
  }
  else {
    /* Receiver in active state, a callback is generated, if enabled, after
       a completed transfer.*/
    dmaStreamDisable(uartp->dmarx);
    uartp->rxstate = UART_RX_COMPLETE;
    if (uartp->config->rxend_cb != NULL)
      uartp->config->rxend_cb(uartp);

    /* If the callback didn't explicitly change state then the receiver
       automatically returns to the idle state.*/
    if (uartp->rxstate == UART_RX_COMPLETE) {
      uartp->rxstate = UART_RX_IDLE;
      set_rx_idle_loop(uartp);
    }
  }
}
Exemplo n.º 2
0
/**
 * @brief   USART initialization.
 * @details This function must be invoked with interrupts disabled.
 *
 * @param[in] uartp     pointer to the @p UARTDriver object
 */
static void usart_start(UARTDriver *uartp) {
  uint32_t cr1;
  USART_TypeDef *u = uartp->usart;

  /* Defensive programming, starting from a clean state.*/
  usart_stop(uartp);

  /* Baud rate setting.*/
  u->BRR = (uint32_t)(uartp->clock / uartp->config->speed);

  /* Resetting eventual pending status flags.*/
  u->ICR = 0xFFFFFFFFU;

  /* Note that some bits are enforced because required for correct driver
     operations.*/
  u->CR2 = uartp->config->cr2 | USART_CR2_LBDIE;
  u->CR3 = uartp->config->cr3 | USART_CR3_DMAT | USART_CR3_DMAR |
                                USART_CR3_EIE;

  /* Mustn't ever set TCIE here - if done, it causes an immediate
     interrupt.*/
  cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE;
  u->CR1 = uartp->config->cr1 | cr1;

  /* Starting the receiver idle loop.*/
  set_rx_idle_loop(uartp);
}
/**
 * @brief   USART initialization.
 * @details This function must be invoked with interrupts disabled.
 *
 * @param[in] uartp     pointer to the @p UARTDriver object
 */
static void usart_start(UARTDriver *uartp) {
  uint16_t cr1;
  USART_TypeDef *u = uartp->usart;

  /* Defensive programming, starting from a clean state.*/
  usart_stop(uartp);

  /* Baud rate setting.*/
  if (uartp->usart == USART1)
    u->BRR = STM32_PCLK2 / uartp->config->speed;
  else
    u->BRR = STM32_PCLK1 / uartp->config->speed;

  /* Resetting eventual pending status flags.*/
  (void)u->SR;  /* SR reset step 1.*/
  (void)u->DR;  /* SR reset step 2.*/
  u->SR = 0;

  /* Note that some bits are enforced because required for correct driver
     operations.*/
  if (uartp->config->txend2_cb == NULL)
    cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE;
  else
    cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE |
          USART_CR1_TCIE;
  u->CR1 = uartp->config->cr1 | cr1;
  u->CR2 = uartp->config->cr2 | USART_CR2_LBDIE;
  u->CR3 = uartp->config->cr3 | USART_CR3_DMAT | USART_CR3_DMAR |
                                USART_CR3_EIE;

  /* Starting the receiver idle loop.*/
  set_rx_idle_loop(uartp);
}
/**
 * @brief   Stops any ongoing receive operation.
 * @note    Stopping a receive operation also suppresses the receive callbacks.
 *
 * @param[in] uartp     pointer to the @p UARTDriver object
 *
 * @return              The number of data frames not received by the
 *                      stopped receive operation.
 *
 * @notapi
 */
size_t uart_lld_stop_receive(UARTDriver *uartp) {
  size_t n;

  dmaStreamDisable(uartp->dmarx);
  n = dmaStreamGetTransactionSize(uartp->dmarx);
  set_rx_idle_loop(uartp);
  return n;
}
Exemplo n.º 5
0
/**
 * @brief   USART initialization.
 * @details This function must be invoked with interrupts disabled.
 *
 * @param[in] uartp     pointer to the @p UARTDriver object
 */
static void usart_start(UARTDriver *uartp) {
  uint16_t cr1;
  USART_TypeDef *u = uartp->usart;

  /* Defensive programming, starting from a clean state.*/
  usart_stop(uartp);

  /* Baud rate setting.*/
#if STM32_HAS_USART6
  if ((uartp->usart == USART1) || (uartp->usart == USART6))
#else
  if (uartp->usart == USART1)
#endif
    u->BRR = STM32_PCLK2 / uartp->config->speed;
  else
    u->BRR = STM32_PCLK1 / uartp->config->speed;

  /* Resetting eventual pending status flags.*/
  (void)u->SR;  /* SR reset step 1.*/
  (void)u->DR;  /* SR reset step 2.*/
  u->SR = 0;

  /* Note that some bits are enforced because required for correct driver
     operations.*/
  u->CR2 = uartp->config->cr2 | USART_CR2_LBDIE;
  u->CR3 = uartp->config->cr3 | USART_CR3_DMAT | USART_CR3_DMAR |
                                USART_CR3_EIE;

  /* Mustn't ever set TCIE here - if done, it causes an immediate
     interrupt.*/
  cr1 = USART_CR1_UE | USART_CR1_PEIE | USART_CR1_TE | USART_CR1_RE;
  u->CR1 = uartp->config->cr1 | cr1;

  /* Starting the receiver idle loop.*/
  set_rx_idle_loop(uartp);
}