diff --git a/nucleo-wb55-dongle-ble/Core/Src/main.c b/nucleo-wb55-dongle-ble/Core/Src/main.c
index fb29bda..ad845fd 100644
--- a/nucleo-wb55-dongle-ble/Core/Src/main.c
+++ b/nucleo-wb55-dongle-ble/Core/Src/main.c
@@ -23,7 +23,7 @@
 
 /* Private includes ----------------------------------------------------------*/
 /* USER CODE BEGIN Includes */
-
+#include "usbd_cdc_if.h"
 /* USER CODE END Includes */
 
 /* Private typedef -----------------------------------------------------------*/
@@ -55,7 +55,9 @@ static void MX_GPIO_Init(void);
 
 /* Private user code ---------------------------------------------------------*/
 /* USER CODE BEGIN 0 */
-
+void usb_receive(uint8_t *buf, uint32_t *len) {
+  CDC_Transmit_FS(buf, *len);  // echo
+}
 /* USER CODE END 0 */
 
 /**
diff --git a/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.c b/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.c
index 88aa4e0..1a107b5 100644
--- a/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.c
+++ b/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.c
@@ -32,7 +32,7 @@
 
 /* USER CODE BEGIN PV */
 /* Private variables ---------------------------------------------------------*/
-
+uint8_t buffer[7];
 /* USER CODE END PV */
 
 /** @addtogroup STM32_USB_OTG_DEVICE_LIBRARY
@@ -129,7 +129,7 @@ static int8_t CDC_Receive_FS(uint8_t* pbuf, uint32_t *Len);
 static int8_t CDC_TransmitCplt_FS(uint8_t *pbuf, uint32_t *Len, uint8_t epnum);
 
 /* USER CODE BEGIN PRIVATE_FUNCTIONS_DECLARATION */
-
+__weak void usb_receive(uint8_t *buf, uint32_t *len) {}
 /* USER CODE END PRIVATE_FUNCTIONS_DECLARATION */
 
 /**
@@ -221,10 +221,16 @@ static int8_t CDC_Control_FS(uint8_t cmd, uint8_t* pbuf, uint16_t length)
   /* 6      | bDataBits  |   1   | Number Data bits (5, 6, 7, 8 or 16).          */
   /*******************************************************************************/
     case CDC_SET_LINE_CODING:
+    	for (int i = 0; i< 7; i++) {
+    		buffer[i] = pbuf[i];
+    	}
 
     break;
 
     case CDC_GET_LINE_CODING:
+    	for (int i = 0; i< 7; i++) {
+    		pbuf[i] = buffer[i];
+    	}
 
     break;
 
@@ -264,6 +270,7 @@ static int8_t CDC_Receive_FS(uint8_t* Buf, uint32_t *Len)
   /* USER CODE BEGIN 6 */
   USBD_CDC_SetRxBuffer(&hUsbDeviceFS, &Buf[0]);
   USBD_CDC_ReceivePacket(&hUsbDeviceFS);
+  usb_receive(Buf, Len);
   return (USBD_OK);
   /* USER CODE END 6 */
 }
diff --git a/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.h b/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.h
index fabb17a..56b3657 100644
--- a/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.h
+++ b/nucleo-wb55-dongle-ble/USB_Device/App/usbd_cdc_if.h
@@ -110,7 +110,7 @@ extern USBD_CDC_ItfTypeDef USBD_Interface_fops_FS;
 uint8_t CDC_Transmit_FS(uint8_t* Buf, uint16_t Len);
 
 /* USER CODE BEGIN EXPORTED_FUNCTIONS */
-
+__weak void usb_receive(uint8_t *buf, uint32_t *len);
 /* USER CODE END EXPORTED_FUNCTIONS */
 
 /**
diff --git a/serial_communication.py b/serial_communication.py
index 1f69a1f..2270c6d 100644
--- a/serial_communication.py
+++ b/serial_communication.py
@@ -29,6 +29,7 @@ def main():
         logger.info(f"received: {x}")
         logger.info(f"in_waiting: {serial_connection.in_waiting}")
 
+        return
         delay = 0.1
         while True:
             logger.info("Set blue LED")