diff --git a/demos/STM32/RT-STM32L152RE-NUCLEO64/mcuconf.h b/demos/STM32/RT-STM32L152RE-NUCLEO64/mcuconf.h
index e014ee8a8..9cfa9a023 100644
--- a/demos/STM32/RT-STM32L152RE-NUCLEO64/mcuconf.h
+++ b/demos/STM32/RT-STM32L152RE-NUCLEO64/mcuconf.h
@@ -187,14 +187,18 @@
 #define STM32_UART_USE_USART1               FALSE
 #define STM32_UART_USE_USART2               FALSE
 #define STM32_UART_USE_USART3               FALSE
-#define STM32_UART_USE_UART4                TRUE
-#define STM32_UART_USE_UART5                TRUE
+#define STM32_UART_USE_UART4                FALSE
+#define STM32_UART_USE_UART5                FALSE
 #define STM32_UART_USART1_IRQ_PRIORITY      12
 #define STM32_UART_USART2_IRQ_PRIORITY      12
 #define STM32_UART_USART3_IRQ_PRIORITY      12
+#define STM32_UART_UART4_IRQ_PRIORITY       12
+#define STM32_UART_UART5_IRQ_PRIORITY       12
 #define STM32_UART_USART1_DMA_PRIORITY      0
 #define STM32_UART_USART2_DMA_PRIORITY      0
 #define STM32_UART_USART3_DMA_PRIORITY      0
+#define STM32_UART_UART4_DMA_PRIORITY       0
+#define STM32_UART_UART5_DMA_PRIORITY       0
 #define STM32_UART_USART1_RX_DMA_STREAM     STM32_DMA_STREAM_ID(1, 5)
 #define STM32_UART_USART1_TX_DMA_STREAM     STM32_DMA_STREAM_ID(1, 4)
 #define STM32_UART_USART2_RX_DMA_STREAM     STM32_DMA_STREAM_ID(1, 6)