diff --git a/main/DAP_handle.c b/main/DAP_handle.c
index e7bd5ab..1aa3f9d 100644
--- a/main/DAP_handle.c
+++ b/main/DAP_handle.c
@@ -236,9 +236,9 @@ int fast_reply(uint8_t *buf, uint32_t length)
 
             #if (USE_WINUSB == 1)
                 uint32_t resLength = item->length;
-                send_stage2_submit_data((usbip_stage2_header *)buf, 0, item->buf, resLength);
+                send_stage2_submit_data_fast((usbip_stage2_header *)buf, 0, item->buf, resLength);
             #else
-                send_stage2_submit_data((usbip_stage2_header *)buf, 0, item->buf, DAP_HANDLE_SIZE);
+                send_stage2_submit_data_fast((usbip_stage2_header *)buf, 0, item->buf, DAP_HANDLE_SIZE);
             #endif
 
 
diff --git a/main/usbip_server.c b/main/usbip_server.c
index 915cfeb..dbd77ea 100644
--- a/main/usbip_server.c
+++ b/main/usbip_server.c
@@ -190,7 +190,7 @@ int emulate(uint8_t *buffer, uint32_t length)
     int command = read_stage2_command((usbip_stage2_header *)buffer, length);
     if (command < 0)
     {
-        return -1;     
+        return -1;
     }
 
     switch (command)
@@ -229,7 +229,7 @@ static int read_stage2_command(usbip_stage2_header *header, uint32_t length)
  *       - ret_submit
  *       - cmd_unlink
  *       - ret_unlink
- * 
+ *
  * @param data Point to packets header
  * @param size Packets header size
  */
@@ -253,7 +253,7 @@ static void pack(void *data, int size)
  *       - ret_submit
  *       - cmd_unlink
  *       - ret_unlink
- * 
+ *
  * @param data Point to packets header
  * @param size  packets header size
  */
@@ -355,6 +355,26 @@ void send_stage2_submit_data(usbip_stage2_header *req_header, int32_t status, co
     }
 }
 
+void send_stage2_submit_data_fast(usbip_stage2_header *req_header, int32_t status, const void *const data, int32_t data_length)
+{
+    const uint8_t * send_buf = (uint8_t *)req_header;
+
+    req_header->base.command = USBIP_STAGE2_RSP_SUBMIT;
+    req_header->base.direction = !(req_header->base.direction);
+
+    memset(&(req_header->u.ret_submit), 0, sizeof(usbip_stage2_header_ret_submit));
+
+    req_header->u.ret_submit.status = status;
+    req_header->u.ret_submit.data_length = data_length;
+
+    pack(req_header, sizeof(usbip_stage2_header));
+
+    // payload
+    memcpy(&send_buf[sizeof(usbip_stage2_header)], data, data_length);
+    send(kSock, send_buf, sizeof(usbip_stage2_header) + data_length, 0);
+}
+
+
 static void handle_unlink(usbip_stage2_header *header)
 {
     os_printf("s2 handling cmd unlink...\r\n");
diff --git a/main/usbip_server.h b/main/usbip_server.h
index 2d0effd..08b6c10 100644
--- a/main/usbip_server.h
+++ b/main/usbip_server.h
@@ -15,5 +15,7 @@ int attach(uint8_t *buffer, uint32_t length);
 int emulate(uint8_t *buffer, uint32_t length);
 void send_stage2_submit_data(usbip_stage2_header *req_header, int32_t status, const void * const data, int32_t data_length);
 void send_stage2_submit(usbip_stage2_header *req_header, int32_t status, int32_t data_length);
+void send_stage2_submit_data_fast(usbip_stage2_header *req_header, int32_t status, const void *const data, int32_t data_length);
+
 
 #endif
\ No newline at end of file