/* The cooperative scheduler requires a normal IRQ service routine to
simply increment the system tick. */
__arm __irq void vPortNonPreemptiveTick( void )
{
/* Increment the tick count - which may wake some tasks but as the
preemptive scheduler is not being used any woken task is not given
processor time no matter what its priority. */
xTaskIncrementTick();
/* Clear the interrupt in the watchdog and EIC. */
WDG->SR = 0x0000;
portCLEAR_EIC();
}
/* This function is called from an asm wrapper, so does not require the __irq
keyword. */
void vPortPreemptiveTick( void )
{
/* Increment the tick counter. */
if( xTaskIncrementTick() != pdFALSE ) {
/* Select a new task to execute. */
vTaskSwitchContext();
}
/* Clear the interrupt in the watchdog and EIC. */
WDG->SR = 0x0000;
portCLEAR_EIC();
}
/* This function is called from an asm wrapper, so does not require the __irq
keyword. */
void vPortPreemptiveTick( void )
{
/* Increment the tick counter. */
vTaskIncrementTick();
/* The new tick value might unblock a task. Ensure the highest task that
is ready to execute is the task that will execute when the tick ISR
exits. */
vTaskSwitchContext();
/* Clear the interrupt in the watchdog and EIC. */
WDG->SR = 0x0000;
portCLEAR_EIC();
}
/* Serial port ISR. This can cause a context switch so is not defined as a
standard ISR using the __irq keyword. Instead a wrapper function is defined
within serialISR.s79 which in turn calls this function. See the port
documentation on the FreeRTOS.org website for more information. */
__arm void vSerialISR( void )
{
unsigned short usStatus;
signed char cChar;
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
/* What caused the interrupt? */
usStatus = UART_FlagStatus( UART0 );
if( usStatus & UART_TxHalfEmpty )
{
/* 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->TxBUFR = cChar;
}
else
{
/* Queue empty, nothing to send so turn off the Tx interrupt. */
serINTERRUPT_OFF();
}
}
if( usStatus & UART_RxBufFull )
{
/* 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->RxBUFR;
xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken );
}
/* 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 );
/* End the interrupt in the EIC. */
portCLEAR_EIC();
}