diff --git a/Core/Inc/stm32f4xx_it.h b/Core/Inc/stm32f4xx_it.h
index a98d381..a25a65a 100644
--- a/Core/Inc/stm32f4xx_it.h
+++ b/Core/Inc/stm32f4xx_it.h
@@ -56,7 +56,9 @@ void DebugMon_Handler(void);
 void PendSV_Handler(void);
 void SysTick_Handler(void);
 void USART1_IRQHandler(void);
+void DMA2_Stream2_IRQHandler(void);
 void OTG_FS_IRQHandler(void);
+void DMA2_Stream7_IRQHandler(void);
 /* USER CODE BEGIN EFP */
 
 /* USER CODE END EFP */
diff --git a/Core/Src/main.c b/Core/Src/main.c
index f1690ba..da059fb 100644
--- a/Core/Src/main.c
+++ b/Core/Src/main.c
@@ -42,14 +42,23 @@
 
 /* Private variables ---------------------------------------------------------*/
 UART_HandleTypeDef huart1;
+DMA_HandleTypeDef hdma_usart1_rx;
+DMA_HandleTypeDef hdma_usart1_tx;
 
 /* USER CODE BEGIN PV */
 
+static const uint8_t uart1_test_message[] = "USART1 DMA TX TEST\r\n";
+static volatile uint32_t uart1_tx_ok_count;
+static volatile uint32_t uart1_tx_busy_count;
+static volatile uint32_t uart1_tx_error_count;
+static volatile uint32_t uart1_tx_complete_count;
+
 /* USER CODE END PV */
 
 /* Private function prototypes -----------------------------------------------*/
 void SystemClock_Config(void);
 static void MX_GPIO_Init(void);
+static void MX_DMA_Init(void);
 static void MX_USART1_UART_Init(void);
 /* USER CODE BEGIN PFP */
 
@@ -89,6 +98,7 @@ int main(void)
 
   /* Initialize all configured peripherals */
   MX_GPIO_Init();
+  MX_DMA_Init();
   MX_USB_DEVICE_Init();
   MX_USART1_UART_Init();
   /* USER CODE BEGIN 2 */
@@ -102,6 +112,26 @@ int main(void)
     /* USER CODE END WHILE */
 
     /* USER CODE BEGIN 3 */
+    HAL_StatusTypeDef uart_status;
+
+    uart_status = HAL_UART_Transmit_DMA(&huart1,
+                                       (uint8_t *)uart1_test_message,
+                                       sizeof(uart1_test_message) - 1U);
+
+    if (uart_status == HAL_OK)
+    {
+      uart1_tx_ok_count++;
+    }
+    else if (uart_status == HAL_BUSY)
+    {
+      uart1_tx_busy_count++;
+    }
+    else
+    {
+      uart1_tx_error_count++;
+    }
+
+    HAL_Delay(1000U);
   }
   /* USER CODE END 3 */
 }
@@ -188,6 +218,25 @@ static void MX_USART1_UART_Init(void)
 
 }
 
+/**
+  * Enable DMA controller clock
+  */
+static void MX_DMA_Init(void)
+{
+
+  /* DMA controller clock enable */
+  __HAL_RCC_DMA2_CLK_ENABLE();
+
+  /* DMA interrupt init */
+  /* DMA2_Stream2_IRQn interrupt configuration */
+  HAL_NVIC_SetPriority(DMA2_Stream2_IRQn, 5, 0);
+  HAL_NVIC_EnableIRQ(DMA2_Stream2_IRQn);
+  /* DMA2_Stream7_IRQn interrupt configuration */
+  HAL_NVIC_SetPriority(DMA2_Stream7_IRQn, 5, 0);
+  HAL_NVIC_EnableIRQ(DMA2_Stream7_IRQn);
+
+}
+
 /**
   * @brief GPIO Initialization Function
   * @param None
@@ -210,6 +259,14 @@ static void MX_GPIO_Init(void)
 
 /* USER CODE BEGIN 4 */
 
+void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
+{
+  if (huart->Instance == USART1)
+  {
+    uart1_tx_complete_count++;
+  }
+}
+
 /* USER CODE END 4 */
 
 /**
diff --git a/Core/Src/stm32f4xx_hal_msp.c b/Core/Src/stm32f4xx_hal_msp.c
index d6f0b6e..cf22fea 100644
--- a/Core/Src/stm32f4xx_hal_msp.c
+++ b/Core/Src/stm32f4xx_hal_msp.c
@@ -22,6 +22,9 @@
 /* USER CODE BEGIN Includes */
 
 /* USER CODE END Includes */
+extern DMA_HandleTypeDef hdma_usart1_rx;
+
+extern DMA_HandleTypeDef hdma_usart1_tx;
 
 /* Private typedef -----------------------------------------------------------*/
 /* USER CODE BEGIN TD */
@@ -105,8 +108,45 @@ void HAL_UART_MspInit(UART_HandleTypeDef* huart)
     GPIO_InitStruct.Alternate = GPIO_AF7_USART1;
     HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
+    /* USART1 DMA Init */
+    /* USART1_RX Init */
+    hdma_usart1_rx.Instance = DMA2_Stream2;
+    hdma_usart1_rx.Init.Channel = DMA_CHANNEL_4;
+    hdma_usart1_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
+    hdma_usart1_rx.Init.PeriphInc = DMA_PINC_DISABLE;
+    hdma_usart1_rx.Init.MemInc = DMA_MINC_ENABLE;
+    hdma_usart1_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    hdma_usart1_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
+    hdma_usart1_rx.Init.Mode = DMA_NORMAL;
+    hdma_usart1_rx.Init.Priority = DMA_PRIORITY_LOW;
+    hdma_usart1_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
+    if (HAL_DMA_Init(&hdma_usart1_rx) != HAL_OK)
+    {
+      Error_Handler();
+    }
+
+    __HAL_LINKDMA(huart,hdmarx,hdma_usart1_rx);
+
+    /* USART1_TX Init */
+    hdma_usart1_tx.Instance = DMA2_Stream7;
+    hdma_usart1_tx.Init.Channel = DMA_CHANNEL_4;
+    hdma_usart1_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
+    hdma_usart1_tx.Init.PeriphInc = DMA_PINC_DISABLE;
+    hdma_usart1_tx.Init.MemInc = DMA_MINC_ENABLE;
+    hdma_usart1_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
+    hdma_usart1_tx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
+    hdma_usart1_tx.Init.Mode = DMA_NORMAL;
+    hdma_usart1_tx.Init.Priority = DMA_PRIORITY_LOW;
+    hdma_usart1_tx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
+    if (HAL_DMA_Init(&hdma_usart1_tx) != HAL_OK)
+    {
+      Error_Handler();
+    }
+
+    __HAL_LINKDMA(huart,hdmatx,hdma_usart1_tx);
+
     /* USART1 interrupt Init */
-    HAL_NVIC_SetPriority(USART1_IRQn, 0, 0);
+    HAL_NVIC_SetPriority(USART1_IRQn, 5, 0);
     HAL_NVIC_EnableIRQ(USART1_IRQn);
     /* USER CODE BEGIN USART1_MspInit 1 */
 
@@ -138,6 +178,10 @@ void HAL_UART_MspDeInit(UART_HandleTypeDef* huart)
     */
     HAL_GPIO_DeInit(GPIOA, GPIO_PIN_9|GPIO_PIN_10);
 
+    /* USART1 DMA DeInit */
+    HAL_DMA_DeInit(huart->hdmarx);
+    HAL_DMA_DeInit(huart->hdmatx);
+
     /* USART1 interrupt DeInit */
     HAL_NVIC_DisableIRQ(USART1_IRQn);
     /* USER CODE BEGIN USART1_MspDeInit 1 */
diff --git a/Core/Src/stm32f4xx_it.c b/Core/Src/stm32f4xx_it.c
index fba995a..47664e9 100644
--- a/Core/Src/stm32f4xx_it.c
+++ b/Core/Src/stm32f4xx_it.c
@@ -56,6 +56,8 @@
 
 /* External variables --------------------------------------------------------*/
 extern PCD_HandleTypeDef hpcd_USB_OTG_FS;
+extern DMA_HandleTypeDef hdma_usart1_rx;
+extern DMA_HandleTypeDef hdma_usart1_tx;
 extern UART_HandleTypeDef huart1;
 /* USER CODE BEGIN EV */
 
@@ -214,6 +216,20 @@ void USART1_IRQHandler(void)
   /* USER CODE END USART1_IRQn 1 */
 }
 
+/**
+  * @brief This function handles DMA2 stream2 global interrupt.
+  */
+void DMA2_Stream2_IRQHandler(void)
+{
+  /* USER CODE BEGIN DMA2_Stream2_IRQn 0 */
+
+  /* USER CODE END DMA2_Stream2_IRQn 0 */
+  HAL_DMA_IRQHandler(&hdma_usart1_rx);
+  /* USER CODE BEGIN DMA2_Stream2_IRQn 1 */
+
+  /* USER CODE END DMA2_Stream2_IRQn 1 */
+}
+
 /**
   * @brief This function handles USB On The Go FS global interrupt.
   */
@@ -228,6 +244,20 @@ void OTG_FS_IRQHandler(void)
   /* USER CODE END OTG_FS_IRQn 1 */
 }
 
+/**
+  * @brief This function handles DMA2 stream7 global interrupt.
+  */
+void DMA2_Stream7_IRQHandler(void)
+{
+  /* USER CODE BEGIN DMA2_Stream7_IRQn 0 */
+
+  /* USER CODE END DMA2_Stream7_IRQn 0 */
+  HAL_DMA_IRQHandler(&hdma_usart1_tx);
+  /* USER CODE BEGIN DMA2_Stream7_IRQn 1 */
+
+  /* USER CODE END DMA2_Stream7_IRQn 1 */
+}
+
 /* USER CODE BEGIN 1 */
 
 /* USER CODE END 1 */
diff --git a/Document/Xinje_XD_XL_PLC_Hardware_Manual_PD01_20240820_v1.3.2.pdf b/Document/Xinje_XD_XL_PLC_Hardware_Manual_PD01_20240820_v1.3.2.pdf
new file mode 100644
index 0000000..947e1e7
Binary files /dev/null and b/Document/Xinje_XD_XL_PLC_Hardware_Manual_PD01_20240820_v1.3.2.pdf differ
diff --git a/Modbus.ioc b/Modbus.ioc
index 741888e..7f8801c 100644
--- a/Modbus.ioc
+++ b/Modbus.ioc
@@ -2,18 +2,42 @@
 CAD.formats=
 CAD.pinconfig=
 CAD.provider=
+Dma.Request0=USART1_RX
+Dma.Request1=USART1_TX
+Dma.RequestsNb=2
+Dma.USART1_RX.0.Direction=DMA_PERIPH_TO_MEMORY
+Dma.USART1_RX.0.FIFOMode=DMA_FIFOMODE_DISABLE
+Dma.USART1_RX.0.Instance=DMA2_Stream2
+Dma.USART1_RX.0.MemDataAlignment=DMA_MDATAALIGN_BYTE
+Dma.USART1_RX.0.MemInc=DMA_MINC_ENABLE
+Dma.USART1_RX.0.Mode=DMA_NORMAL
+Dma.USART1_RX.0.PeriphDataAlignment=DMA_PDATAALIGN_BYTE
+Dma.USART1_RX.0.PeriphInc=DMA_PINC_DISABLE
+Dma.USART1_RX.0.Priority=DMA_PRIORITY_LOW
+Dma.USART1_RX.0.RequestParameters=Instance,Direction,PeriphInc,MemInc,PeriphDataAlignment,MemDataAlignment,Mode,Priority,FIFOMode
+Dma.USART1_TX.1.Direction=DMA_MEMORY_TO_PERIPH
+Dma.USART1_TX.1.FIFOMode=DMA_FIFOMODE_DISABLE
+Dma.USART1_TX.1.Instance=DMA2_Stream7
+Dma.USART1_TX.1.MemDataAlignment=DMA_MDATAALIGN_BYTE
+Dma.USART1_TX.1.MemInc=DMA_MINC_ENABLE
+Dma.USART1_TX.1.Mode=DMA_NORMAL
+Dma.USART1_TX.1.PeriphDataAlignment=DMA_PDATAALIGN_BYTE
+Dma.USART1_TX.1.PeriphInc=DMA_PINC_DISABLE
+Dma.USART1_TX.1.Priority=DMA_PRIORITY_LOW
+Dma.USART1_TX.1.RequestParameters=Instance,Direction,PeriphInc,MemInc,PeriphDataAlignment,MemDataAlignment,Mode,Priority,FIFOMode
 File.Version=6
 GPIO.groupedBy=
 KeepUserPlacement=false
 Mcu.CPN=STM32F407IGT6
 Mcu.Family=STM32F4
-Mcu.IP0=NVIC
-Mcu.IP1=RCC
-Mcu.IP2=SYS
-Mcu.IP3=USART1
-Mcu.IP4=USB_DEVICE
-Mcu.IP5=USB_OTG_FS
-Mcu.IPNb=6
+Mcu.IP0=DMA
+Mcu.IP1=NVIC
+Mcu.IP2=RCC
+Mcu.IP3=SYS
+Mcu.IP4=USART1
+Mcu.IP5=USB_DEVICE
+Mcu.IP6=USB_OTG_FS
+Mcu.IPNb=7
 Mcu.Name=STM32F407I(E-G)Tx
 Mcu.Package=LQFP176
 Mcu.Pin0=PH0-OSC_IN
@@ -31,6 +55,8 @@ Mcu.UserName=STM32F407IGTx
 MxCube.Version=6.17.0
 MxDb.Version=DB.6.0.170
 NVIC.BusFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
+NVIC.DMA2_Stream2_IRQn=true\:5\:0\:true\:false\:true\:false\:true\:true
+NVIC.DMA2_Stream7_IRQn=true\:5\:0\:true\:false\:true\:false\:true\:true
 NVIC.DebugMonitor_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 NVIC.ForceEnableDMAVector=true
 NVIC.HardFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
@@ -41,7 +67,7 @@ NVIC.PendSV_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 NVIC.PriorityGroup=NVIC_PRIORITYGROUP_4
 NVIC.SVCall_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 NVIC.SysTick_IRQn=true\:15\:0\:false\:false\:true\:false\:true\:false
-NVIC.USART1_IRQn=true\:0\:0\:false\:false\:true\:true\:true\:true
+NVIC.USART1_IRQn=true\:5\:0\:true\:false\:true\:true\:true\:true
 NVIC.UsageFault_IRQn=true\:0\:0\:false\:false\:true\:false\:false\:false
 PA10.Mode=Asynchronous
 PA10.Signal=USART1_RX
@@ -96,7 +122,7 @@ ProjectManager.ToolChainLocation=
 ProjectManager.UAScriptAfterPath=
 ProjectManager.UAScriptBeforePath=
 ProjectManager.UnderRoot=false
-ProjectManager.functionlistsort=1-SystemClock_Config-RCC-false-HAL-false,2-MX_GPIO_Init-GPIO-false-HAL-true,3-MX_USB_DEVICE_Init-USB_DEVICE-false-HAL-false,4-MX_USART1_UART_Init-USART1-false-HAL-true
+ProjectManager.functionlistsort=1-SystemClock_Config-RCC-false-HAL-false,2-MX_GPIO_Init-GPIO-false-HAL-true,3-MX_DMA_Init-DMA-false-HAL-true,4-MX_USB_DEVICE_Init-USB_DEVICE-false-HAL-false,5-MX_USART1_UART_Init-USART1-false-HAL-true
 RCC.48MHZClocksFreq_Value=48000000
 RCC.AHBFreq_Value=168000000
 RCC.APB1CLKDivider=RCC_HCLK_DIV4