esp-open-rtos/extras/serial-driver/serial_driver.c
Johan Kanflo 9d80dc441f IRQ driven RX on UART0
See examples/terminal/ for usage
2015-08-08 00:22:28 +02:00

119 lines
4 KiB
C

/*
* The MIT License (MIT)
*
* Copyright (c) 2015 Johan Kanflo (github.com/kanflo)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <esp8266.h>
#include <espressif/esp8266/esp8266.h>
#include <espressif/esp8266/uart_register.h>
#include <FreeRTOS.h>
#include <semphr.h>
#if (configUSE_COUNTING_SEMAPHORES == 0)
#error "You need to define configUSE_COUNTING_SEMAPHORES in a local FreeRTOSConfig.h, see examples/terminal/FreeRTOSConfig.h"
#endif
// IRQ driven UART RX driver for ESP8266 written for use with esp-open-rtos
// TODO: Handle UART1
#define UART0_RX_SIZE (81)
#ifndef UART0
#define UART0 (0)
#endif
static xSemaphoreHandle uart0_sem = NULL;
static char rx_buf[UART0_RX_SIZE];
static uint8_t rd_pos = 0;
static uint8_t wr_pos = 0;
static bool inited = false;
static void uart0_rx_init(void);
IRAM void uart0_rx_handler(void)
{
// TODO: Handle UART1, see reg 0x3ff20020, bit2, bit0 represents uart1 and uart0 respectively
if (UART_RXFIFO_FULL_INT_ST != (READ_PERI_REG(UART_INT_ST(UART0)) & UART_RXFIFO_FULL_INT_ST)) {
return;
}
WRITE_PERI_REG(UART_INT_CLR(UART0), UART_RXFIFO_FULL_INT_CLR);
while (READ_PERI_REG(UART_STATUS(UART0)) & (UART_RXFIFO_CNT << UART_RXFIFO_CNT_S)) {
char ch = READ_PERI_REG(UART_FIFO(UART0)) & 0xff;
uint8_t wr_next = (wr_pos+1) % UART0_RX_SIZE;
if (wr_next != rd_pos) {
rx_buf[wr_pos] = ch;
wr_pos = (wr_pos+1) % UART0_RX_SIZE;
xSemaphoreGiveFromISR(uart0_sem, NULL);
}
}
}
uint32_t uart0_num_char(void)
{
uint32_t count;
if (!inited) uart0_rx_init();
_xt_isr_mask(1 << INUM_UART);
if (rd_pos > wr_pos) count = rd_pos - wr_pos;
else count = wr_pos - rd_pos;
_xt_isr_unmask(1 << INUM_UART);
return count;
}
// _read_r in core/newlib_syscalls.c will be skipped in favour of this function
long _read_r(struct _reent *r, int fd, char *ptr, int len)
{
if (!inited) uart0_rx_init();
for(int i = 0; i < len; i++) {
char ch;
if (xSemaphoreTake(uart0_sem, portMAX_DELAY)) {
_xt_isr_mask(1 << INUM_UART);
ch = rx_buf[rd_pos];
rd_pos = (rd_pos+1) % UART0_RX_SIZE;
_xt_isr_unmask(1 << INUM_UART);
ptr[i] = ch;
}
}
return len;
}
static void uart0_rx_init(void)
{
int trig_lvl = 1;
uart0_sem = xSemaphoreCreateCounting(UART0_RX_SIZE, 0);
_xt_isr_attach(INUM_UART, uart0_rx_handler);
_xt_isr_unmask(1 << INUM_UART);
//clear rx and tx fifo,not ready
SET_PERI_REG_MASK(UART_CONF0(UART0), UART_RXFIFO_RST | UART_TXFIFO_RST);
CLEAR_PERI_REG_MASK(UART_CONF0(UART0), UART_RXFIFO_RST | UART_TXFIFO_RST);
//set rx fifo trigger
WRITE_PERI_REG(UART_CONF1(UART0), (trig_lvl & UART_RXFIFO_FULL_THRHD) << UART_RXFIFO_FULL_THRHD_S);
//clear all interrupt
WRITE_PERI_REG(UART_INT_CLR(UART0), 0xffff);
//enable rx_interrupt
SET_PERI_REG_MASK(UART_INT_ENA(UART0), UART_RXFIFO_FULL_INT_ENA);
inited = true;
}