From c3f66f060189a40dbd5dd65efe381045ed099256 Mon Sep 17 00:00:00 2001
From: Tobias Antonsson <tobias@bitcraze.se>
Date: Wed, 2 Sep 2015 14:25:20 +0200
Subject: [PATCH] Fixed syslink priority issue causing corrupt syslink
 packages.

---
 config/FreeRTOSConfig.h    | 2 +-
 config/config.h            | 2 +-
 drivers/src/uart_syslink.c | 8 +++++++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/config/FreeRTOSConfig.h b/config/FreeRTOSConfig.h
index 985fb8a960..6ef9965c10 100644
--- a/config/FreeRTOSConfig.h
+++ b/config/FreeRTOSConfig.h
@@ -87,7 +87,7 @@
 #define configUSE_MALLOC_FAILED_HOOK 1
 #define configTIMER_TASK_STACK_DEPTH configMINIMAL_STACK_SIZE
 
-#define configMAX_PRIORITIES		( ( unsigned portBASE_TYPE ) 5 )
+#define configMAX_PRIORITIES		( ( unsigned portBASE_TYPE ) 6 )
 #define configMAX_CO_ROUTINE_PRIORITIES ( 2 )
 
 /* Set the following definitions to 1 to include the API function, or zero
diff --git a/config/config.h b/config/config.h
index c07bf3c138..02b3dd16a4 100644
--- a/config/config.h
+++ b/config/config.h
@@ -74,7 +74,7 @@
 #define MEM_TASK_PRI            1
 #define PARAM_TASK_PRI          1
 #define STABILIZER_TASK_PRI     4
-#define SYSLINK_TASK_PRI        3
+#define SYSLINK_TASK_PRI        5
 #define USBLINK_TASK_PRI        3
 #define PROXIMITY_TASK_PRI      0
 //CF1
diff --git a/drivers/src/uart_syslink.c b/drivers/src/uart_syslink.c
index ce0d92e658..bda3a79eaf 100644
--- a/drivers/src/uart_syslink.c
+++ b/drivers/src/uart_syslink.c
@@ -322,13 +322,19 @@ void uartIsr(void)
       xHigherPriorityTaskWoken = pdFALSE;
       xSemaphoreGiveFromISR(waitUntilSendDone, &xHigherPriorityTaskWoken);
     }
+    USART_ClearITPendingBit(UART_TYPE, USART_IT_TXE);
   }
-  USART_ClearITPendingBit(UART_TYPE, USART_IT_TXE);
   if (USART_GetITStatus(UART_TYPE, USART_IT_RXNE))
   {
+    // Note: UART interrupt pending bit cleared by reading DR
     rxDataInterrupt = USART_ReceiveData(UART_TYPE) & 0x00FF;
     xQueueSendFromISR(uartDataDelivery, &rxDataInterrupt, &xHigherPriorityTaskWoken);
   }
+
+  if (xHigherPriorityTaskWoken)
+  {
+    vPortYieldFromISR();
+  }
 }
 
 void uartTxenFlowctrlIsr()