Added an implementation of a serial port with a pin remap for the F1 family.

Added an implementation of  aserial port for the F3 family.

f1/usart/src/usart1_remap.c

+#include "usart1.h"
+
+#define     USART                    USART1
+#define     USART_ENABLE_CLK         __HAL_RCC_USART1_CLK_ENABLE()
+#define     USART_IRQn               USART1_IRQn
+#define     USART_IRQHandler         USART1_IRQHandler
+
+#define     USART_TX_PIN             GPIO_PIN_6 
+#define     USART_TX_GPIO_PORT       GPIOB
+#define     USART_ENABLE_TX_GPIO_CLK __HAL_RCC_GPIOB_CLK_ENABLE()
+
+#define     USART_RX_PIN             GPIO_PIN_7
+#define     USART_RX_GPIO_PORT       GPIOB
+#define     USART_ENABLE_RX_GPIO_CLK __HAL_RCC_GPIOB_CLK_ENABLE()
+
+/* DMA configuration */
+#define     USART_DMA                DMA1
+#define     USART_ENABLE_DMA_CLK     __HAL_RCC_DMA1_CLK_ENABLE()
+
+#define     USART_TX_DMA_CHANNEL     DMA1_Channel4
+#define     USART_RX_DMA_CHANNEL     DMA1_Channel5
+
+#define     USART_DMA_TX_IRQn        DMA1_Channel4_IRQn
+#define     USART_DMA_RX_IRQn        DMA1_Channel5_IRQn
+#define     USART_DMA_TX_IRQHandler  DMA1_Channel4_IRQHandler
+#define     USART_DMA_RX_IRQHandler  DMA1_Channel5_IRQHandler
+
+// private variables
+UART_HandleTypeDef Uart1Handle;
+DMA_HandleTypeDef usart1_hdma_tx;
+DMA_HandleTypeDef usart1_hdma_rx;
+TComm *usart1_comm_dev;
+
+// interrupt handlers
+void USART_IRQHandler(void)
+{
+  unsigned char data,ret;
+  uint32_t source;
+
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_RXNE) != RESET)
+  {
+    if(__HAL_UART_GET_IT_SOURCE(&Uart1Handle, UART_IT_RXNE) !=RESET)
+    {
+      __HAL_UART_CLEAR_FLAG(&Uart1Handle,UART_FLAG_RXNE);
+      data=(uint8_t)(Uart1Handle.Instance->DR & (uint8_t)0x00FF);
+      // call the reception function
+      if(!comm_do_irq_receive(usart1_comm_dev,data))
+        __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_RXNE);
+    }
+  }
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_TC) != RESET)
+  {
+    if(__HAL_UART_GET_IT_SOURCE(&Uart1Handle, UART_IT_TC) !=RESET)
+    {
+      __HAL_UART_CLEAR_FLAG(&Uart1Handle,UART_FLAG_TC);
+      ret=comm_do_irq_send(usart1_comm_dev,&data);
+      if(ret==0x01)
+        Uart1Handle.Instance->DR=data;
+      else if(ret==0x00)
+        __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_TC);
+    }
+  }
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_PE) != RESET)// parity error
+  {
+    if(__HAL_UART_GET_IT_SOURCE(&Uart1Handle, UART_IT_PE) !=RESET)
+    {
+      __HAL_UART_CLEAR_PEFLAG(&Uart1Handle);
+    }
+  }
+  source=__HAL_UART_GET_IT_SOURCE(&Uart1Handle, UART_IT_ERR);
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_FE) != RESET)// frame error
+  {
+    if(source !=RESET)
+    {
+      __HAL_UART_CLEAR_FEFLAG(&Uart1Handle);
+    }
+  }
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_NE) != RESET)// noise error
+  {
+    if(source !=RESET)
+    {
+      __HAL_UART_CLEAR_NEFLAG(&Uart1Handle);
+    }
+  }
+  if(__HAL_UART_GET_FLAG(&Uart1Handle, UART_FLAG_ORE) != RESET)// overrun error
+  {
+    if(source !=RESET)
+    {
+      __HAL_UART_CLEAR_OREFLAG(&Uart1Handle);
+    }
+  }
+}
+
+void USART_DMA_TX_IRQHandler(void)
+{
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx,__HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_TE) != RESET)
+    {
+      /* Disable the transfer error interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_TE);
+      /* Clear the transfer error flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmatx));
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx,__HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_TC) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_TC);
+      /* Clear the transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmatx));
+      CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+      HAL_DMA_Abort(Uart1Handle.hdmatx);
+      // call the user function
+      comm_do_dma_send(usart1_comm_dev);
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_HT) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_HT);
+      /* Clear the half transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmatx));
+    }
+  }
+}
+
+void USART_DMA_RX_IRQHandler(void)
+{
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx,__HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_TE) != RESET)
+    {
+      /* Disable the transfer error interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_TE);
+      /* Clear the transfer error flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmarx));
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx,__HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_TC) != RESET)
+    {
+      /* Disable the transfer complete interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_TC);
+      /* Clear the transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmarx));
+      CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+      HAL_DMA_Abort(Uart1Handle.hdmarx);
+      // call the user function
+      comm_do_dma_receive(usart1_comm_dev);
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_HT) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_HT);
+      /* Clear the half transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmarx));
+    }
+  }
+}
+
+/* public functions*/
+void usart1_init(TComm *comm_dev,UART_InitTypeDef *conf,TUSART_IRQ_Priorities *priorities)
+{
+  GPIO_InitTypeDef GPIO_InitStructure;
+
+  /* Enable GPIO clock */
+  USART_ENABLE_TX_GPIO_CLK;
+  USART_ENABLE_RX_GPIO_CLK;
+  USART_ENABLE_DMA_CLK;
+  // configure the GPIO pins
+
+  USART_ENABLE_CLK;
+
+  /* Configure USART Tx and Rx as alternate function push-pull */
+  GPIO_InitStructure.Pin       = USART_TX_PIN;
+  GPIO_InitStructure.Mode      = GPIO_MODE_AF_PP;
+  GPIO_InitStructure.Speed     = GPIO_SPEED_HIGH;
+  HAL_GPIO_Init(USART_TX_GPIO_PORT, &GPIO_InitStructure);
+
+  GPIO_InitStructure.Pin       = USART_RX_PIN;
+  GPIO_InitStructure.Pull      = GPIO_NOPULL;
+  GPIO_InitStructure.Mode      = GPIO_MODE_INPUT;
+  HAL_GPIO_Init(USART_RX_GPIO_PORT, &GPIO_InitStructure);
+
+  __HAL_AFIO_REMAP_USART1_ENABLE();
+
+  Uart1Handle.Instance          = USART;
+  usart1_config(comm_dev,conf);
+
+  if(comm_dev->use_dma)
+  {
+    // configure the DMA channels
+    usart1_hdma_tx.Instance                 = USART_TX_DMA_CHANNEL;
+    usart1_hdma_tx.Init.Direction           = DMA_MEMORY_TO_PERIPH;
+    usart1_hdma_tx.Init.PeriphInc           = DMA_PINC_DISABLE;
+    usart1_hdma_tx.Init.MemInc              = DMA_MINC_ENABLE;
+    usart1_hdma_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    usart1_hdma_tx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
+    usart1_hdma_tx.Init.Mode                = DMA_NORMAL;
+    usart1_hdma_tx.Init.Priority            = DMA_PRIORITY_LOW;
+
+    HAL_DMA_Init(&usart1_hdma_tx);
+
+    /* Associate the initialized DMA handle to the UART handle */
+    __HAL_LINKDMA(&Uart1Handle, hdmatx, usart1_hdma_tx);
+
+    /* Configure the DMA handler for reception process */
+    usart1_hdma_rx.Instance                 = USART_RX_DMA_CHANNEL;
+    usart1_hdma_rx.Init.Direction           = DMA_PERIPH_TO_MEMORY;
+    usart1_hdma_rx.Init.PeriphInc           = DMA_PINC_DISABLE;
+    usart1_hdma_rx.Init.MemInc              = DMA_MINC_ENABLE;
+    usart1_hdma_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    usart1_hdma_rx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
+    usart1_hdma_rx.Init.Mode                = DMA_NORMAL;
+    usart1_hdma_rx.Init.Priority            = DMA_PRIORITY_HIGH;
+
+    HAL_DMA_Init(&usart1_hdma_rx);
+
+    /* Associate the initialized DMA handle to the the UART handle */
+    __HAL_LINKDMA(&Uart1Handle, hdmarx, usart1_hdma_rx);
+  }
+  usart1_set_priorities(comm_dev,priorities);
+
+  /* Initialize the comm structure */
+  comm_dev->send_irq=usart1_send_irq;
+  comm_dev->enable_tx_irq=usart1_enable_tx_irq;
+  comm_dev->receive_irq=usart1_receive_irq;
+  comm_dev->cancel_receive_irq=usart1_cancel_receive_irq;
+  if(comm_dev->use_dma)
+  {
+    comm_dev->send_dma=usart1_send_dma;
+    comm_dev->receive_dma=usart1_receive_dma;
+    comm_dev->cancel_receive_dma=usart1_cancel_receive_dma;
+  }
+  comm_dev->irq_send_cb=0x00000000;
+  comm_dev->irq_receive_cb=0x00000000;
+  comm_dev->dma_send_cb=0x00000000;
+  comm_dev->dma_receive_cb=0x00000000;
+
+  /* initialize internal variables */
+  usart1_comm_dev=comm_dev;
+}
+
+void usart1_config(TComm *comm_dev,UART_InitTypeDef *conf)
+{
+  Uart1Handle.Init.BaudRate     = conf->BaudRate;
+  Uart1Handle.Init.WordLength   = conf->WordLength;
+  Uart1Handle.Init.StopBits     = conf->StopBits;
+  Uart1Handle.Init.Parity       = conf->Parity;
+  Uart1Handle.Init.Mode         = conf->Mode;
+  Uart1Handle.Init.HwFlowCtl    = conf->HwFlowCtl;
+  Uart1Handle.Init.OverSampling = conf->OverSampling;
+  HAL_UART_Init(&Uart1Handle);
+}
+
+void usart1_set_priorities(TComm *comm_dev,TUSART_IRQ_Priorities *priorities)
+{
+  HAL_NVIC_SetPriority(USART_IRQn, priorities->irq_priority,priorities->irq_subpriority);
+  HAL_NVIC_EnableIRQ(USART_IRQn);
+  if(comm_dev->use_dma)
+  {
+    HAL_NVIC_SetPriority(USART_DMA_TX_IRQn, priorities->dma_tx_priority,priorities->dma_tx_subpriority);
+    HAL_NVIC_EnableIRQ(USART_DMA_TX_IRQn);
+    HAL_NVIC_SetPriority(USART_DMA_RX_IRQn, priorities->dma_rx_priority,priorities->dma_rx_subpriority);
+    HAL_NVIC_EnableIRQ(USART_DMA_RX_IRQn);
+  }
+}
+
+/* IRQ functions */
+unsigned char usart1_send_irq(unsigned char first_byte)
+{
+  __HAL_UART_CLEAR_FLAG(&Uart1Handle,UART_FLAG_TC);
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_TC);
+  Uart1Handle.Instance->DR=first_byte;
+
+  return 0x00;
+}
+
+unsigned char usart1_enable_tx_irq(void)
+{
+  __HAL_UART_CLEAR_FLAG(&Uart1Handle,UART_FLAG_TC);
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_TC);
+
+  return 0x00;
+}
+
+unsigned char usart1_receive_irq(void)
+{
+  /* enable the rx interrupt */
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_RXNE);
+
+  return 0x00;
+}
+
+unsigned char usart1_cancel_receive_irq(void)
+{
+  /* disable the rx interrupt */
+  __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_RXNE);
+
+  return 0x00;
+}
+
+/* DMA functions */
+unsigned char usart1_send_dma(unsigned char *data,unsigned short int length)
+{
+  HAL_DMA_Start_IT(Uart1Handle.hdmatx,(uint32_t)data,(uint32_t)&Uart1Handle.Instance->DR,length);
+  /* Clear the TC flag in the SR register by writing 0 to it */
+  __HAL_UART_CLEAR_FLAG(&Uart1Handle,UART_FLAG_TC);
+  /* Enable the DMA transfer for transmit request by setting the DMAT bit
+     in the UART CR3 register */
+  SET_BIT(Uart1Handle.Instance->CR3, USART_CR3_DMAT);
+
+  return 0x00;
+}
+
+unsigned char usart1_receive_dma(unsigned char *data,unsigned short int length)
+{
+  HAL_DMA_Start_IT(Uart1Handle.hdmarx,(uint32_t)&Uart1Handle.Instance->DR,(uint32_t)data,length);
+  SET_BIT(Uart1Handle.Instance->CR3, USART_CR3_DMAR);
+
+  return 0x00;
+}
+
+unsigned char usart1_cancel_receive_dma(void)
+{
+  CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+  HAL_DMA_Abort(Uart1Handle.hdmarx);
+
+  return 0x00;
+}
+

f3/usart/include/usart1.h

+#ifndef USART1_F3_H
+#define USART1_F3_H
+
+#include "stm32f3xx_hal.h"
+#include "usart_common.h"
+#include "comm.h"
+
+/* public functions */
+void usart1_init(TComm *comm_dev,UART_InitTypeDef *conf,TUSART_IRQ_Priorities *priorities);
+void usart1_config(TComm *comm_dev,UART_InitTypeDef *conf);
+void usart1_set_priorities(TComm *comm_dev,TUSART_IRQ_Priorities *priorities);
+/* IRQ functions */
+unsigned char usart1_send_irq(unsigned char first_byte);
+unsigned char usart1_enable_tx_irq(void);
+unsigned char usart1_receive_irq(void);
+unsigned char usart1_cancel_receive_irq(void);
+/* DMA functions */
+unsigned char usart1_send_dma(unsigned char *data,unsigned short int length);
+unsigned char usart1_receive_dma(unsigned char *data,unsigned short int length);
+unsigned char usart1_cancel_receive_dma(void);
+
+#endif

f3/usart/include/usart_common.h

+#ifndef USART_COMMON_F3_H
+#define USART_COMMON_F3_H
+
+typedef struct
+{
+  unsigned char irq_priority;
+  unsigned char irq_subpriority;
+  unsigned char dma_rx_priority;
+  unsigned char dma_rx_subpriority;
+  unsigned char dma_tx_priority;
+  unsigned char dma_tx_subpriority;
+}TUSART_IRQ_Priorities;
+
+#endif

f3/usart/src/usart1.c

+#include "usart1.h"
+
+#define     USART                    USART1
+#define     USART_ENABLE_CLK         __USART1_CLK_ENABLE()
+#define     USART_IRQn               USART1_IRQn
+#define     USART_IRQHandler         USART1_IRQHandler
+
+#define     USART_TX_PIN             GPIO_PIN_4                
+#define     USART_TX_GPIO_PORT       GPIOC
+#define     USART_ENABLE_TX_GPIO_CLK __GPIOC_CLK_ENABLE()
+
+#define     USART_RX_PIN             GPIO_PIN_5
+#define     USART_RX_GPIO_PORT       GPIOC
+#define     USART_ENABLE_RX_GPIO_CLK __GPIOC_CLK_ENABLE()
+
+/* DMA configuration */
+#define     USART_DMA                DMA1
+#define     USART_ENABLE_DMA_CLK     __DMA1_CLK_ENABLE()
+
+#define     USART_TX_DMA_CHANNEL     DMA1_Channel4
+#define     USART_RX_DMA_CHANNEL     DMA1_Channel5
+
+#define     USART_DMA_TX_IRQn        DMA1_Channel4_IRQn
+#define     USART_DMA_RX_IRQn        DMA1_Channel5_IRQn
+#define     USART_DMA_TX_IRQHandler  DMA1_Channel4_IRQHandler
+#define     USART_DMA_RX_IRQHandler  DMA1_Channel5_IRQHandler
+
+// private variables
+UART_HandleTypeDef Uart1Handle;
+DMA_HandleTypeDef usart1_hdma_tx;
+DMA_HandleTypeDef usart1_hdma_rx;
+TComm *usart1_comm_dev;
+
+// interrupt handlers
+void USART_IRQHandler(void)
+{
+  unsigned char data,ret;
+
+  /* USART parity error interrupt occured ------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_PE) != RESET)
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_PE) != RESET)
+    {
+      __HAL_USART_CLEAR_IT(&Uart1Handle, USART_IT_PE);
+    }
+  }
+
+  /* USART frame error interrupt occured -------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_FE) != RESET)
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_ERR) != RESET)
+    {
+      __HAL_USART_CLEAR_IT(&Uart1Handle, USART_IT_FE);
+    }
+  }
+
+  /* USART noise error interrupt occured -------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_NE) != RESET)
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_ERR) != RESET)
+    {
+      __HAL_USART_CLEAR_IT(&Uart1Handle, USART_IT_NE);
+    }
+  }
+
+  /* USART Over-Run interrupt occured ----------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_ORE) != RESET)
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_ERR) != RESET)
+    {
+      __HAL_USART_CLEAR_IT(&Uart1Handle, USART_IT_ORE);
+    }
+  }
+
+  /* USART in mode Receiver --------------------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_RXNE) != RESET)
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_RXNE) != RESET)
+    {
+      __HAL_USART_CLEAR_IT(&Uart1Handle, USART_IT_RXNE);
+      data=(uint8_t)(Uart1Handle.Instance->RDR & (uint8_t)0x00FF);
+      // call the reception function
+      if(!comm_do_irq_receive(usart1_comm_dev,data))
+        __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_RXNE);
+    }
+  }
+
+  /* USART in mode Transmitter -----------------------------------------------*/
+  if(__HAL_USART_GET_IT(&Uart1Handle, USART_IT_TC) != RESET) 
+  {
+    if(__HAL_USART_GET_IT_SOURCE(&Uart1Handle, USART_IT_TC) != RESET)
+    {
+      __HAL_UART_CLEAR_IT(&Uart1Handle,UART_IT_TC);
+      ret=comm_do_irq_send(usart1_comm_dev,&data);
+      if(ret==0x01)
+        Uart1Handle.Instance->TDR=data;
+      else if(ret==0x00)
+        __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_TC);
+    }
+  }
+}
+
+void USART_DMA_TX_IRQHandler(void)
+{
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx,__HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_TE) != RESET)
+    {
+      /* Disable the transfer error interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_TE);
+      /* Clear the transfer error flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmatx));
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx,__HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_TC) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_TC);
+      /* Clear the transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmatx));
+      CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+      HAL_DMA_Abort(Uart1Handle.hdmatx);
+      // call the user function
+      comm_do_dma_send(usart1_comm_dev);
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmatx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmatx, DMA_IT_HT) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmatx, DMA_IT_HT);
+      /* Clear the half transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmatx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmatx));
+    }
+  }
+}
+
+void USART_DMA_RX_IRQHandler(void)
+{
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx,__HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_TE) != RESET)
+    {
+      /* Disable the transfer error interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_TE);
+      /* Clear the transfer error flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_TE_FLAG_INDEX(Uart1Handle.hdmarx));
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx,__HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_TC) != RESET)
+    {
+      /* Disable the transfer complete interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_TC);
+      /* Clear the transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_TC_FLAG_INDEX(Uart1Handle.hdmarx));
+      CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+      HAL_DMA_Abort(Uart1Handle.hdmarx);
+      // call the user function
+      comm_do_dma_receive(usart1_comm_dev);
+    }
+  }
+  if(__HAL_DMA_GET_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmarx)) != RESET)
+  {
+    if(__HAL_DMA_GET_IT_SOURCE(Uart1Handle.hdmarx, DMA_IT_HT) != RESET)
+    {
+      /* Disable the half transfer interrupt */
+      __HAL_DMA_DISABLE_IT(Uart1Handle.hdmarx, DMA_IT_HT);
+      /* Clear the half transfer complete flag */
+      __HAL_DMA_CLEAR_FLAG(Uart1Handle.hdmarx, __HAL_DMA_GET_HT_FLAG_INDEX(Uart1Handle.hdmarx));
+    }
+  }
+}
+
+/* public functions*/
+void usart1_init(TComm *comm_dev,UART_InitTypeDef *conf,TUSART_IRQ_Priorities *priorities)
+{
+  GPIO_InitTypeDef GPIO_InitStructure;
+
+  /* Enable GPIO clock */
+  USART_ENABLE_TX_GPIO_CLK;
+  USART_ENABLE_RX_GPIO_CLK;
+  USART_ENABLE_DMA_CLK;
+  // configure the GPIO pins
+
+  /* Configure USART Tx and Rx as alternate function push-pull */
+  GPIO_InitStructure.Pin       = USART_TX_PIN;
+  GPIO_InitStructure.Mode      = GPIO_MODE_AF_PP;
+  GPIO_InitStructure.Pull      = GPIO_PULLUP;
+  GPIO_InitStructure.Speed     = GPIO_SPEED_HIGH;
+  GPIO_InitStructure.Alternate = GPIO_AF7_USART1;
+  HAL_GPIO_Init(USART_TX_GPIO_PORT, &GPIO_InitStructure);
+
+  GPIO_InitStructure.Pin       = USART_RX_PIN;
+  HAL_GPIO_Init(USART_RX_GPIO_PORT, &GPIO_InitStructure);
+
+  USART_ENABLE_CLK;
+
+  Uart1Handle.Instance          = USART;
+  usart1_config(comm_dev,conf);
+
+  if(comm_dev->use_dma)
+  {
+    // configure the DMA channels
+    usart1_hdma_tx.Instance                 = USART_TX_DMA_CHANNEL;
+    usart1_hdma_tx.Init.Direction           = DMA_MEMORY_TO_PERIPH;
+    usart1_hdma_tx.Init.PeriphInc           = DMA_PINC_DISABLE;
+    usart1_hdma_tx.Init.MemInc              = DMA_MINC_ENABLE;
+    usart1_hdma_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    usart1_hdma_tx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
+    usart1_hdma_tx.Init.Mode                = DMA_NORMAL;
+    usart1_hdma_tx.Init.Priority            = DMA_PRIORITY_LOW;
+
+    HAL_DMA_Init(&usart1_hdma_tx);
+
+    /* Associate the initialized DMA handle to the UART handle */
+    __HAL_LINKDMA(&Uart1Handle, hdmatx, usart1_hdma_tx);
+
+    /* Configure the DMA handler for reception process */
+    usart1_hdma_rx.Instance                 = USART_RX_DMA_CHANNEL;
+    usart1_hdma_rx.Init.Direction           = DMA_PERIPH_TO_MEMORY;
+    usart1_hdma_rx.Init.PeriphInc           = DMA_PINC_DISABLE;
+    usart1_hdma_rx.Init.MemInc              = DMA_MINC_ENABLE;
+    usart1_hdma_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    usart1_hdma_rx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
+    usart1_hdma_rx.Init.Mode                = DMA_NORMAL;
+    usart1_hdma_rx.Init.Priority            = DMA_PRIORITY_HIGH;
+
+    HAL_DMA_Init(&usart1_hdma_rx);
+
+    /* Associate the initialized DMA handle to the the UART handle */
+    __HAL_LINKDMA(&Uart1Handle, hdmarx, usart1_hdma_rx);
+  }
+  usart1_set_priorities(comm_dev,priorities);
+
+  /* Initialize the comm structure */
+  comm_dev->send_irq=usart1_send_irq;
+  comm_dev->enable_tx_irq=usart1_enable_tx_irq;
+  comm_dev->receive_irq=usart1_receive_irq;
+  comm_dev->cancel_receive_irq=usart1_cancel_receive_irq;
+  if(comm_dev->use_dma)
+  {
+    comm_dev->send_dma=usart1_send_dma;
+    comm_dev->receive_dma=usart1_receive_dma;
+    comm_dev->cancel_receive_dma=usart1_cancel_receive_dma;
+  }
+  comm_dev->irq_send_cb=0x00000000;
+  comm_dev->irq_receive_cb=0x00000000;
+  comm_dev->dma_send_cb=0x00000000;
+  comm_dev->dma_receive_cb=0x00000000;
+
+  /* initialize internal variables */
+  usart1_comm_dev=comm_dev;
+}
+
+void usart1_config(TComm *comm_dev,UART_InitTypeDef *conf)
+{
+  Uart1Handle.Init.BaudRate     = conf->BaudRate;
+  Uart1Handle.Init.WordLength   = conf->WordLength;
+  Uart1Handle.Init.StopBits     = conf->StopBits;
+  Uart1Handle.Init.Parity       = conf->Parity;
+  Uart1Handle.Init.Mode         = conf->Mode;
+  Uart1Handle.Init.HwFlowCtl    = conf->HwFlowCtl;
+  Uart1Handle.Init.OverSampling = conf->OverSampling;
+  Uart1Handle.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
+  HAL_UART_Init(&Uart1Handle);
+}
+
+void usart1_set_priorities(TComm *comm_dev,TUSART_IRQ_Priorities *priorities)
+{
+  HAL_NVIC_SetPriority(USART_IRQn, priorities->irq_priority,priorities->irq_subpriority);
+  HAL_NVIC_EnableIRQ(USART_IRQn);
+  if(comm_dev->use_dma)
+  {
+    HAL_NVIC_SetPriority(USART_DMA_TX_IRQn, priorities->dma_tx_priority,priorities->dma_tx_subpriority);
+    HAL_NVIC_EnableIRQ(USART_DMA_TX_IRQn);
+    HAL_NVIC_SetPriority(USART_DMA_RX_IRQn, priorities->dma_rx_priority,priorities->dma_rx_subpriority);
+    HAL_NVIC_EnableIRQ(USART_DMA_RX_IRQn);
+  }
+}
+
+/* IRQ functions */
+unsigned char usart1_send_irq(unsigned char first_byte)
+{
+  __HAL_UART_CLEAR_IT(&Uart1Handle,UART_IT_TC);
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_TC);
+  Uart1Handle.Instance->TDR=first_byte;
+
+  return 0x00;
+}
+
+unsigned char usart1_enable_tx_irq(void)
+{
+  __HAL_UART_CLEAR_IT(&Uart1Handle,UART_IT_TC);
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_TC);
+
+  return 0x00;
+}
+
+unsigned char usart1_receive_irq(void)
+{
+  /* enable the rx interrupt */
+  __HAL_UART_ENABLE_IT(&Uart1Handle, UART_IT_RXNE);
+
+  return 0x00;
+}
+
+unsigned char usart1_cancel_receive_irq(void)
+{
+  /* disable the rx interrupt */
+  __HAL_UART_DISABLE_IT(&Uart1Handle, UART_IT_RXNE);
+
+  return 0x00;
+}
+
+/* DMA functions */
+unsigned char usart1_send_dma(unsigned char *data,unsigned short int length)
+{
+  HAL_DMA_Start_IT(Uart1Handle.hdmatx,(uint32_t)data,(uint32_t)&Uart1Handle.Instance->TDR,length);
+  /* Clear the TC flag in the SR register by writing 0 to it */
+  __HAL_UART_CLEAR_IT(&Uart1Handle,UART_IT_TC);
+  /* Enable the DMA transfer for transmit request by setting the DMAT bit
+     in the UART CR3 register */
+  SET_BIT(Uart1Handle.Instance->CR3, USART_CR3_DMAT);
+
+  return 0x00;
+}
+
+unsigned char usart1_receive_dma(unsigned char *data,unsigned short int length)
+{
+  HAL_DMA_Start_IT(Uart1Handle.hdmarx,(uint32_t)&Uart1Handle.Instance->RDR,(uint32_t)data,length);
+  SET_BIT(Uart1Handle.Instance->CR3, USART_CR3_DMAR);
+
+  return 0x00;
+}
+
+unsigned char usart1_cancel_receive_dma(void)
+{
+  CLEAR_BIT(Uart1Handle.Instance->CR3, (USART_CR3_DMAT | USART_CR3_DMAR));
+  HAL_DMA_Abort(Uart1Handle.hdmarx);
+
+  return 0x00;
+}
+