diff --git a/flight/PiOS/STM32F10x/pios_usart.c b/flight/PiOS/STM32F10x/pios_usart.c
index 1c087738c..176992cb9 100644
--- a/flight/PiOS/STM32F10x/pios_usart.c
+++ b/flight/PiOS/STM32F10x/pios_usart.c
@@ -180,9 +180,15 @@ int32_t PIOS_USART_Init(uint32_t * usart_id, const struct pios_usart_cfg * cfg)
 
 	/* Configure USART Interrupts */
 	switch ((uint32_t)usart_dev->cfg->regs) {
-	case (uint32_t)USART1: PIOS_USART_1_id = (uint32_t)usart_dev;
-	case (uint32_t)USART2: PIOS_USART_2_id = (uint32_t)usart_dev;
-	case (uint32_t)USART3: PIOS_USART_3_id = (uint32_t)usart_dev;
+	case (uint32_t)USART1:
+		PIOS_USART_1_id = (uint32_t)usart_dev;
+		break;
+	case (uint32_t)USART2:
+		PIOS_USART_2_id = (uint32_t)usart_dev;
+		break;
+	case (uint32_t)USART3:
+		PIOS_USART_3_id = (uint32_t)usart_dev;
+		break;
 	}
 	NVIC_Init(&usart_dev->cfg->irq.init);
 	USART_ITConfig(usart_dev->cfg->regs, USART_IT_RXNE, ENABLE);