diff --git a/Demo/ARM7_STR71x_IAR/Library/uart.c b/Demo/ARM7_STR71x_IAR/Library/uart.c
index c299345ca..8e01a97ed 100644
--- a/Demo/ARM7_STR71x_IAR/Library/uart.c
+++ b/Demo/ARM7_STR71x_IAR/Library/uart.c
@@ -19,6 +19,8 @@
 
 #include "uart.h"
 
+extern u16 UART_FlagStatus(UART_TypeDef *UARTx);
+
 /*******************************************************************************
 * Function Name  : UART_Init
 * Description    : This function initializes the selected UART.