giomba/nes-proj
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Added optional interrupt-based transmission, based on the ringbuf library

Browse Source
This commit is contained in:
adamdunkels 2009-03-01 20:40:30 +00:00
parent d813d343c5
commit 6ab7ac0598
1 changed files with 57 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
cpu/msp430/dev/uart1.c
View File

@ -26,7 +26,7 @@
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)$Id: uart1.c,v 1.9 2009/02/24 21:31:10 adamdunkels Exp $
* @(#)$Id: uart1.c,v 1.10 2009/03/01 20:40:30 adamdunkels Exp $
*/
/*
@ -42,13 +42,27 @@
#include "dev/leds.h"
#include "dev/watchdog.h"
#include "lib/ringbuf.h"
static int (*uart1_input_handler)(unsigned char c);
static uint8_t rx_in_progress;
static volatile uint8_t transmitting;
#define TX_WITH_INTERRUPT 1
#if TX_WITH_INTERRUPT
#define TXBUFSIZE 64
static struct ringbuf txbuf;
static uint8_t txbuf_data[TXBUFSIZE];
#endif /* TX_WITH_INTERRUPT */
/*---------------------------------------------------------------------------*/
uint8_t
uart1_active(void)
{
return ((~ UTCTL1) & TXEPT) | rx_in_progress;
return ((~ UTCTL1) & TXEPT) | rx_in_progress | transmitting;
}
/*---------------------------------------------------------------------------*/
void
@ -60,12 +74,30 @@ uart1_set_input(int (*input)(unsigned char c))
void
uart1_writeb(unsigned char c)
{
#if TX_WITH_INTERRUPT
/* Put the outgoing byte on the transmission buffer. If the buffer
is full, we just keep on trying to put the byte into the buffer
until it is possible to put it there. */
while(ringbuf_put(&txbuf, c) == 0) {
watchdog_periodic();
}
/* If there is no transmission going, we need to start it by putting
the first byte into the UART. */
if(transmitting == 0) {
transmitting = 1;
TXBUF1 = ringbuf_get(&txbuf);
}
#else /* TX_WITH_INTERRUPT */
watchdog_periodic();
/* Loop until the transmission buffer is available. */
while((IFG2 & UTXIFG1) == 0);
/* Transmit the data. */
TXBUF1 = c;
#endif /* TX_WITH_INTERRUPT */
}
/*---------------------------------------------------------------------------*/
#if ! WITH_UIP /* If WITH_UIP is defined, putchar() is defined by the SLIP driver */
@ -127,12 +159,17 @@ uart1_init(unsigned long ubr)
rx_in_progress = 0;
IE2 |= URXIE1; /* Enable USART1 RX interrupt */
transmitting = 0;
IE2 |= URXIE1; /* Enable USART1 RX interrupt */
#if TX_WITH_INTERRUPT
IE2 |= UTXIE1; /* Enable USART1 RX interrupt */
ringbuf_init(&txbuf, txbuf_data, sizeof(txbuf_data));
#endif /* TX_WITH_INTERRUPT */
}
/*---------------------------------------------------------------------------*/
interrupt(UART1RX_VECTOR)
uart1_interrupt(void)
uart1_rx_interrupt(void)
{
ENERGEST_ON(ENERGEST_TYPE_IRQ);
@ -159,3 +196,19 @@ uart1_interrupt(void)
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
#if TX_WITH_INTERRUPT
interrupt(UART1TX_VECTOR)
uart1_tx_interrupt(void)
{
ENERGEST_ON(ENERGEST_TYPE_IRQ);
if(ringbuf_elements(&txbuf) == 0) {
transmitting = 0;
} else {
TXBUF1 = ringbuf_get(&txbuf);
}
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
#endif /* TX_WITH_INTERRUPT */
/*---------------------------------------------------------------------------*/