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#include "project.h"
#define BUFFER_SIZE 256
#define BIG_BUFFER_SIZE 600
ring_t rx1_ring;
static uint8_t rx1_ring_buf[BUFFER_SIZE];
ring_t tx1_ring;
static uint8_t tx1_ring_buf[BUFFER_SIZE];
ring_t rx2_ring;
static uint8_t rx2_ring_buf[BUFFER_SIZE];
ring_t tx2_ring;
static uint8_t tx2_ring_buf[BIG_BUFFER_SIZE];
void
usart1_isr (void)
{
uint8_t data;
/* Check if we were called because of RXNE. */
if (((USART_CR1 (USART1) & USART_CR1_RXNEIE) != 0) &&
((USART_SR (USART1) & USART_SR_RXNE) != 0))
{
/* Retrieve the data from the peripheral. */
data = usart_recv (USART1);
ring_write_byte (&rx1_ring, data);
}
/* Check if we were called because of TXE. */
if (((USART_CR1 (USART1) & USART_CR1_TXEIE) != 0) &&
((USART_SR (USART1) & USART_SR_TXE) != 0))
{
if (ring_read_byte (&tx1_ring, &data))
{
/*No more data, Disable the TXE interrupt, it's no longer needed. */
USART_CR1 (USART1) &= ~USART_CR1_TXEIE;
}
else
{
usart_send (USART1, data);
}
}
}
void
usart2_isr (void)
{
uint8_t data;
/* Check if we were called because of RXNE. */
if (((USART_CR1 (USART2) & USART_CR1_RXNEIE) != 0) &&
((USART_SR (USART2) & USART_SR_RXNE) != 0))
{
/* Retrieve the data from the peripheral. */
data = usart_recv (USART2);
ring_write_byte (&rx2_ring, data);
}
/* Check if we were called because of TXE. */
if (((USART_CR1 (USART2) & USART_CR1_TXEIE) != 0) &&
((USART_SR (USART2) & USART_SR_TXE) != 0))
{
if (ring_read_byte (&tx2_ring, &data))
{
/*No more data, Disable the TXE interrupt, it's no longer needed. */
USART_CR1 (USART2) &= ~USART_CR1_TXEIE;
}
else
{
usart_send_blocking (USART2, data);
}
}
}
int
_write (int file, char *ptr, int len)
{
int ret;
if (file == 1)
{
ret = ring_write (&tx1_ring, (uint8_t *) ptr, len);
if (ret < 0)
ret = -ret;
USART_CR1 (USART1) |= USART_CR1_TXEIE;
return ret;
}
errno = EIO;
return -1;
}
void
usart1_queue (uint8_t d)
{
ring_write_byte (&tx1_ring, d);
USART_CR1 (USART1) |= USART_CR1_TXEIE;
}
void
usart2_queue (uint8_t d)
{
ring_write_byte (&tx2_ring, d);
USART_CR1 (USART2) |= USART_CR1_TXEIE;
}
void
usart2_drain (void)
{
while (!ring_empty (&tx2_ring));
}
void
usart1_drain (void)
{
while (!ring_empty (&tx1_ring));
}
void
usart_init (void)
{
rcc_periph_clock_enable (RCC_USART1);
rcc_periph_clock_enable (RCC_USART2);
rcc_periph_clock_enable (RCC_USART3);
ring_init (&rx1_ring, rx1_ring_buf, sizeof (rx1_ring_buf));
ring_init (&tx1_ring, tx1_ring_buf, sizeof (tx1_ring_buf));
ring_init (&rx2_ring, rx2_ring_buf, sizeof (rx2_ring_buf));
ring_init (&tx2_ring, tx2_ring_buf, sizeof (tx2_ring_buf));
/* Enable the USART1,2 interrupt. */
nvic_enable_irq (NVIC_USART1_IRQ);
nvic_enable_irq (NVIC_USART2_IRQ);
/* Map pins, and set usart2 to have pull ups */
gpio_set_mode (GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART1_TX);
gpio_set_mode (GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT,
GPIO_USART1_RX);
gpio_set_mode (GPIOA, GPIO_MODE_OUTPUT_50_MHZ,
GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO_USART2_TX);
gpio_set_mode (GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_PULL_UPDOWN,
GPIO_USART2_RX);
gpio_set (GPIOA, GPIO_USART2_RX);
/* Setup UART1 parameters. */
usart_set_baudrate (USART1, 38400);
usart_set_databits (USART1, 8);
usart_set_stopbits (USART1, USART_STOPBITS_1);
usart_set_parity (USART1, USART_PARITY_NONE);
usart_set_flow_control (USART1, USART_FLOWCONTROL_NONE);
usart_set_mode (USART1, USART_MODE_TX_RX);
/* Setup UART2 parameters. */
usart_set_baudrate (USART2, 9600);
usart_set_databits (USART2, 8);
usart_set_stopbits (USART2, USART_STOPBITS_1);
usart_set_parity (USART2, USART_PARITY_NONE);
usart_set_flow_control (USART2, USART_FLOWCONTROL_NONE);
usart_set_mode (USART2, USART_MODE_TX_RX);
/* Enable USART1,2 Receive interrupt. */
USART_CR1 (USART1) |= USART_CR1_RXNEIE;
USART_CR1 (USART2) |= USART_CR1_RXNEIE;
/* Finally enable the USARTs. */
usart_enable (USART1);
usart_enable (USART2);
}
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