diff --git a/STM32F1/variants/nucleo_f103rb/board/board.h b/STM32F1/variants/nucleo_f103rb/board/board.h
index 5bac55f..5c909ab 100644
--- a/STM32F1/variants/nucleo_f103rb/board/board.h
+++ b/STM32F1/variants/nucleo_f103rb/board/board.h
@@ -102,6 +102,11 @@
 /**
  * Note: there is no USB in this board.
  */
+ // Roger Clark. These USB disconnect pin definitions have been added as a temporary fix in order that the this board compiles
+ // following changes to add usb serial to other boards
+ // I will remove them when the code in the core usb_serial.cpp has been tidied up so that they are no longer needed.
+#define BOARD_USB_DISC_DEV        GPIOB
+#define BOARD_USB_DISC_BIT        10
 
 /* Pin aliases: these give the GPIO port/bit for each pin as an
  * enum. These are optional, but recommended. They make it easier to