// the isr's...
static void uart_tx_irq( void )
{
unsigned char c;
{
uart_get_tx_data_type handler;
BSP_CRITICAL_STATEMENT( handler = uart_tx_handler );
// if not currently in suspend mode and a handler exists
if( uart_tx_suspend == false && handler != NULL )
{
if( (*handler)( &c ) != false ) // if data available, reset the interrupt
{
UART_SEND( UART_NUMBER, UART_LOCATION, c ); // send the byte
}
else // if no data suspend transmission
{
uart_tx_message_suspend( handler );
UART_IRQ_FLAG_SET( UART_NUMBER, UART_LOCATION, TX );
}
}
else
{
bspIState_t istate;
BSP_ENTER_CRITICAL_SECTION( istate );
// if we are in suspended mode or we just sent an xon or xoff character
// while transmits were disabled or the message has been completely sent,
// then simply disable irq's so we don't get stuck in an infinite loop
UART_IRQ_DISABLE( UART_NUMBER, UART_LOCATION, TX );
UART_IRQ_FLAG_SET( UART_NUMBER, UART_LOCATION, TX );
BSP_EXIT_CRITICAL_SECTION( istate );
}
}
return;
}
/******************************************************************************
* @fn uart1_tx_irq
*
* @brief TX interrupt service routine
*
* input parameters
*
* output parameters
*
* @return
*/
void uart0_tx_irq( void )
{
unsigned char c;
uart_get_tx_data_type handler;
BSP_CRITICAL_STATEMENT( handler = uart0_tx_handler );
/* if a handler exists */
if( handler != NULL )
{
if( (*handler)( &c ) != false ) /* if this is not the last byte to send */
{
bspIState_t intState;
BSP_ENTER_CRITICAL_SECTION( intState );
/* only reset the interrupt flag if we have additional data to send
* that way, if we are done then the interrupt is still pending and
* will be immediately entered upon re-enabling it.*/
UART_IRQ_FLAG_CLR( UART_NUMBER_0, UART0_LOCATION, TX ); /* eset the interrupt */
BSP_EXIT_CRITICAL_SECTION( intState );
}
else
{
bspIState_t intState;
BSP_ENTER_CRITICAL_SECTION( intState );
/* we're done sending data. since we left the interrupt pending,
* disable it so we don't re-enter the isr. the interrupt will be
* re-enabled when there is another message to send. */
UART_IRQ_DISABLE( UART_NUMBER_0, UART0_LOCATION, TX );
/* no more data to send, reset the handler to flag not busy */
uart0_tx_handler = NULL;
BSP_EXIT_CRITICAL_SECTION( intState );
}
UART_SEND( UART_NUMBER_0, UART0_LOCATION, c ); /* send the byte */
}
else /* if no handler exists?!?!?!? */
/* something went wrong, disable interrupts so we don't get stuck here */
UART_IRQ_DISABLE( UART_NUMBER_0, UART0_LOCATION, TX );
return;
}
// user interface functions
void uart_init( void )
{
volatile unsigned int i;
bspIState_t istate;
BSP_ENTER_CRITICAL_SECTION( istate );
// disable the receive and transmit interrupts for the moment
UART_IRQ_DISABLE( UART_NUMBER, UART_LOCATION, TX );
UART_IRQ_DISABLE( UART_NUMBER, UART_LOCATION, RX );
BSP_EXIT_CRITICAL_SECTION( istate );
// make sure the handler functions are cleared in case we are re-initialized
uart_tx_handler = NULL;
uart_rx_handler = NULL;
// clear transmit suspend semaphore
uart_tx_suspend = false;
// initialize the uart interface for operations
UART_INIT( UART_NUMBER,
UART_LOCATION,
UART_FLOW_CONTROL, // enable/disable flow control
UART_PARITY_MODE, // enable/disable parity
UART_STOP_BITS, // number of stop bits
UART_BAUD_RATE ); // baud rate to use
i = UART_BAUD_RATE >> 5; // delay approximately 1 bit time
while( --i != 0 ) // give the uart some time to initialize
; // null statement
// enable receive interrupts, they are always welcome.
UART_IRQ_ENABLE( UART_NUMBER, UART_LOCATION, RX );
return;
}
/******************************************************************************
* @fn uart_init
*
* @brief Configures UART and sets up transmit and receive interrupts
*
* input parameters
*
* output parameters
*
* @return
*/
void uart_init( void )
{
volatile unsigned int i;
/* make sure the handler functions are cleared in case we are re-initialized */
uart1_tx_handler = NULL;
uart0_tx_handler = NULL;
uart_rx_handler = NULL;
/* initialize the uart interface for operations */
UART_INIT( UART_NUMBER_1,
UART_LOCATION_2,
UART_FLOW_CONTROL, /* enable/disable flow control */
UART_PARITY_MODE, /* enable/disable parity */
UART_STOP_BITS, /* number of stop bits */
UART1_BAUD_RATE ); /* baud rate to use */
i = UART1_BAUD_RATE >> 5; /* delay approximately 1 bit time */
while( --i != 0 ) /* give the uart some time to initialize */
; /* null statement */
/* set the interrupt flag so that a transmit interrupt will be pending
* that way when a message is sent and the irq is enabled, the interrupt
* will happen immediately to start the transmission */
UART_IRQ_FLAG_SET( UART_NUMBER_1, UART1_LOCATION, TX ); /* set the interrupt */
/* enable receive interrupts, they are always welcome. */
UART_IRQ_ENABLE( UART_NUMBER_1, UART1_LOCATION, RX );
/* initialize the uart interface for operations */
UART_INIT( UART_NUMBER_0,
UART_LOCATION_2,
UART_FLOW_CONTROL, /* enable/disable flow control */
UART_PARITY_MODE, /* enable/disable parity */
UART_STOP_BITS, /* number of stop bits */
UART0_BAUD_RATE ); /* baud rate to use */
UART_IRQ_FLAG_SET( UART_NUMBER_0, UART0_LOCATION, TX ); /* set the interrupt */
UART_IRQ_DISABLE(UART_NUMBER_0,UART_LOCATION_2,RX);
return;
}
