diff --git a/modbus/modbus.c b/modbus/modbus.c
new file mode 100644
index 0000000..d36e38c
--- /dev/null
+++ b/modbus/modbus.c
@@ -0,0 +1,78 @@
+#include "stm32f4xx.h"
+#include "hardware.h"
+#include "ucos_ii.h"
+#include "os.h"
+#include "app_cfg.h"
+#include "sys_cfg.h"
+
+extern OS_EVENT* ModbusReceived;       /*接收到modbus请求报文*/
+extern OS_EVENT* ModbusAssembled;      /*modbus响应帧组装完成*/
+
+/*USART接收空闲中断*/
+void USART1_IRQHandler(void)
+{
+    OSIntEnter();   /*进入中断*/
+
+    uint32_t temp;
+    uint16_t rxLenRemain;
+    
+    if(USART_GetITStatus(USART1, USART_IT_IDLE) == SET)
+    {
+        /*在计算数据长度之前先关闭DMA接收通道，防止计算过程中DMA继续转运数据*/
+        DMA_Cmd(DMA2_Stream2, DISABLE);
+
+        /*计算数据长度*/
+        rxLenRemain = DMA_GetCurrDataCounter(DMA2_Stream2);
+        ModbusRxLen = MODBUS_RX_BUF_SIZE - rxLenRemain;
+
+        if(ModbusRxLen != 0)
+        {
+            OSSemPost(ModbusReceived);
+        }
+        
+        /*重启DMA*/
+        DMA_SetCurrDataCounter(DMA2_Stream2, MODBUS_RX_BUF_SIZE);
+        DMA_Cmd(DMA2_Stream2, ENABLE);
+
+        /*清除IDLE中断标志位*/
+        temp = USART1->SR;
+        temp = USART1->DR;
+    }
+    
+    OSIntExit();    /*退出中断*/
+}
+
+
+/*modbus响应帧发送*/
+void ModbusSend(uint8_t *txBuf, uint16_t len)
+{
+    /*先关闭DMA发送通道*/
+    DMA_Cmd(DMA2_Stream7, DISABLE);
+
+    /*等待DMA关闭*/
+    while (DMA_GetCmdStatus(DMA2_Stream7) != DISABLE); 
+    
+    /*配置发送地址和长度*/
+    DMA_MemoryTargetConfig(DMA2_Stream7, (uint32_t)txBuf, DMA_Memory_0);     
+    DMA_SetCurrDataCounter(DMA2_Stream7, len);
+    
+    /*启动 DMA 发送*/
+    DMA_Cmd(DMA2_Stream7, ENABLE);
+}
+
+/*modbus响应帧发送任务*/
+void AppTaskModbusSend (void *p_arg)
+{
+
+
+}
+
+
+/*modbus协议帧解析任务*/
+void AppTaskModbusParse (void *p_arg)
+{
+    
+    
+}
+
+
diff --git a/modbus/modbus.h b/modbus/modbus.h
new file mode 100644
index 0000000..63359a7
--- /dev/null
+++ b/modbus/modbus.h
@@ -0,0 +1,26 @@
+#ifndef __MODBUS_H
+#define __MODBUS_H
+
+#include "ucos_ii.h"
+
+/*
+ * Modbus task synchronization objects.
+ *
+ * ModbusReceived:
+ *     USART IDLE ISR -> parse task
+ * ModbusAssembled:
+ *     parse task -> send task
+ * ModbusTxCompleted:
+ *     USART TC ISR -> send task
+ * ModbusTxBufferFree:
+ *     ownership of the single transmit buffer
+ */
+extern OS_EVENT *ModbusReceived;
+extern OS_EVENT *ModbusAssembled;
+extern OS_EVENT *ModbusTxCompleted;
+extern OS_EVENT *ModbusTxBufferFree;
+
+void AppTaskModbusParse(void *p_arg);
+void AppTaskModbusSend(void *p_arg);
+
+#endif