struct ao_fifo ao_usart_rx_fifo;
struct ao_fifo ao_usart_tx_fifo;
-uint8_t ao_usart_tx_started;
+uint8_t ao_usart_tx_avail;
+uint8_t ao_usart_tx_avail_min;
+
+#define LPC_USART_TX_FIFO_SIZE 16
void
ao_debug_out(char c)
static void
_ao_serial_tx_start(void)
{
- if (!ao_fifo_empty(ao_usart_tx_fifo) & !ao_usart_tx_started)
- {
- ao_usart_tx_started = 1;
+ if (!ao_fifo_empty(ao_usart_tx_fifo) && ao_usart_tx_avail) {
+ ao_usart_tx_avail--;
+ if (ao_usart_tx_avail < ao_usart_tx_avail_min)
+ ao_usart_tx_avail_min = ao_usart_tx_avail;
ao_fifo_remove(ao_usart_tx_fifo, lpc_usart.rbr_thr);
}
}
void
lpc_usart_isr(void)
{
+ uint8_t wake_input = 0;
(void) lpc_usart.iir_fcr;
while (lpc_usart.lsr & (1 << LPC_USART_LSR_RDR)) {
char c = lpc_usart.rbr_thr;
if (!ao_fifo_full(ao_usart_rx_fifo))
ao_fifo_insert(ao_usart_rx_fifo, c);
- ao_wakeup(&ao_usart_rx_fifo);
- if (stdin)
- ao_wakeup(&ao_stdin_ready);
+ wake_input = 1;
}
if (lpc_usart.lsr & (1 << LPC_USART_LSR_THRE)) {
- ao_usart_tx_started = 0;
+ ao_usart_tx_avail = LPC_USART_TX_FIFO_SIZE;
_ao_serial_tx_start();
ao_wakeup(&ao_usart_tx_fifo);
}
+ if (wake_input) {
+ ao_wakeup(&ao_usart_rx_fifo);
+ if (stdin)
+ ao_wakeup(&ao_stdin_ready);
+ }
}
int
-_ao_serial_pollchar(void)
+_ao_serial0_pollchar(void)
{
int c;
}
char
-ao_serial_getchar(void)
+ao_serial0_getchar(void)
{
int c;
ao_arch_block_interrupts();
- while ((c = _ao_serial_pollchar()) == AO_READ_AGAIN)
+ while ((c = _ao_serial0_pollchar()) == AO_READ_AGAIN)
ao_sleep(&ao_usart_rx_fifo);
ao_arch_release_interrupts();
return (char) c;
}
void
-ao_serial_putchar(char c)
+ao_serial0_putchar(char c)
{
ao_arch_block_interrupts();
while (ao_fifo_full(ao_usart_tx_fifo))
}
void
-ao_serial_drain(void)
+ao_serial0_drain(void)
{
ao_arch_block_interrupts();
while (!ao_fifo_empty(ao_usart_tx_fifo))
#include "ao_serial_lpc.h"
void
-ao_serial_set_speed(uint8_t speed)
+ao_serial0_set_speed(uint8_t speed)
{
if (speed > AO_SERIAL_SPEED_115200)
return;
(1 << LPC_USART_FCR_TXFIFORES) |
(LPC_USART_FCR_RXTL_1 << LPC_USART_FCR_RXTL));
+ ao_usart_tx_avail = LPC_USART_TX_FIFO_SIZE;
+ ao_usart_tx_avail_min = LPC_USART_TX_FIFO_SIZE;
+
/* 8 n 1 */
lpc_usart.lcr = ((LPC_USART_LCR_WLS_8 << LPC_USART_LCR_WLS) |
(LPC_USART_LCR_SBS_1 << LPC_USART_LCR_SBS) |
lpc_usart.hden = ((0 << LPC_USART_HDEN_HDEN));
/* Set baud rate */
- ao_serial_set_speed(AO_SERIAL_SPEED_9600);
+ ao_serial0_set_speed(AO_SERIAL_SPEED_9600);
/* Enable interrupts */
lpc_usart.ier = ((1 << LPC_USART_IER_RBRINTEN) |
lpc_nvic_set_enable(LPC_ISR_USART_POS);
lpc_nvic_set_priority(LPC_ISR_USART_POS, 0);
#if USE_SERIAL_0_STDIN
- ao_add_stdio(_ao_serial_pollchar,
- ao_serial_putchar,
+ ao_add_stdio(_ao_serial0_pollchar,
+ ao_serial0_putchar,
NULL);
#endif
}