FreeRTOS-Kernel/Demo/ARM7_STR75x_GCC/serial/serialISR.c

/*
    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.

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*/

/*-----------------------------------------------------------
 * Components that can be compiled to either ARM or THUMB mode are
 * contained in serial.c  The ISR routines, which can only be compiled
 * to ARM mode, are contained in this file.
 *----------------------------------------------------------*/



/* Library includes. */
#include "75x_uart.h"

/* Scheduler includes. */
#include "FreeRTOS.h"
#include "queue.h"

static xQueueHandle xRxedChars;
static xQueueHandle xCharsForTx;
static portBASE_TYPE volatile *pxQueueEmpty;

void vConfigureQueues( xQueueHandle xQForRx, xQueueHandle xQForTx, portBASE_TYPE volatile *pxEmptyFlag )
{
	xRxedChars = xQForRx;
	xCharsForTx = xQForTx;
	pxQueueEmpty = pxEmptyFlag;
}
/*-----------------------------------------------------------*/

void vSerialISR( void )
{
signed char cChar;
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;

	do
	{
		if( UART0->MIS & UART_IT_Transmit )
		{
			/* The interrupt was caused by the THR becoming empty.  Are there any
			more characters to transmit? */
			if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xHigherPriorityTaskWoken ) == pdTRUE )
			{
				/* A character was retrieved from the queue so can be sent to the
				THR now. */
				UART0->DR = cChar;
			}
			else
			{
				*pxQueueEmpty = pdTRUE;		
			}		

			UART_ClearITPendingBit( UART0, UART_IT_Transmit );
		}
	
		if( UART0->MIS & UART_IT_Receive )
		{
			/* The interrupt was caused by a character being received.  Grab the
			character from the RHR and place it in the queue of received
			characters. */
			cChar = UART0->DR;
			xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken );
			UART_ClearITPendingBit( UART0, UART_IT_Receive );
		}
	} while( UART0->MIS );

	/* If a task was woken by either a character being received or a character
	being transmitted then we may need to switch to another task. */
	portEND_SWITCHING_ISR( xHigherPriorityTaskWoken );
}