rt-thread/bsp/nrf51822/drivers/uart.c

202 lines
4.9 KiB
C

/*
* File : uart.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2015 RT-Thread Develop Team
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rt-thread.org/license/LICENSE
*
*/
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <rthw.h>
#include <rtdevice.h>
#include "board.h"
#include "uart.h"
#include <nrf_gpio.h>
#define UART_RX_BUFSZ 512
rt_uint8_t rx_buffer[UART_RX_BUFSZ];
struct nrf51822_uart
{
struct rt_device parent;
struct rt_ringbuffer rx_rb;
} uart_device;
void UART0_IRQHandler(void)
{
rt_ubase_t level;
struct nrf51822_uart* uart = &uart_device;
level = rt_hw_interrupt_disable();
// Wait for RXD data to be received
while (NRF_UART0->EVENTS_RXDRDY != 1) ;
NRF_UART0->EVENTS_RXDRDY = 0;
rt_hw_interrupt_enable(level);
/* [Handling the data received over UART] */
rt_ringbuffer_putchar_force(&(uart->rx_rb), (rt_uint8_t)NRF_UART0->RXD);
/* invoke callback */
if(uart->parent.rx_indicate != RT_NULL)
{
uart->parent.rx_indicate(&uart->parent, rt_ringbuffer_data_len(&uart->rx_rb));
}
}
static rt_err_t rt_uart_init (rt_device_t dev)
{
/* UART Initialization and Enable */
/** @snippet [Configure UART RX and TX pin] */
nrf_gpio_cfg_output(TX_PIN_NUMBER);
nrf_gpio_cfg_input(RX_PIN_NUMBER, NRF_GPIO_PIN_NOPULL);
NRF_UART0->PSELTXD = TX_PIN_NUMBER;
NRF_UART0->PSELRXD = RX_PIN_NUMBER;
/** @snippet [Configure UART RX and TX pin] */
if (HWFC)
{
nrf_gpio_cfg_output(RTS_PIN_NUMBER);
nrf_gpio_cfg_input(CTS_PIN_NUMBER, NRF_GPIO_PIN_NOPULL);
NRF_UART0->PSELCTS = CTS_PIN_NUMBER;
NRF_UART0->PSELRTS = RTS_PIN_NUMBER;
NRF_UART0->CONFIG = (UART_CONFIG_HWFC_Enabled << UART_CONFIG_HWFC_Pos);
}
NRF_UART0->BAUDRATE = (UART_BAUDRATE_BAUDRATE_Baud38400 << UART_BAUDRATE_BAUDRATE_Pos);
NRF_UART0->ENABLE = (UART_ENABLE_ENABLE_Enabled << UART_ENABLE_ENABLE_Pos);
NRF_UART0->TASKS_STARTTX = 1;
NRF_UART0->TASKS_STARTRX = 1;
NRF_UART0->EVENTS_RXDRDY = 0;
NRF_UART0->INTENSET = (UART_INTENSET_RXDRDY_Enabled << UART_INTENSET_RXDRDY_Pos);
NVIC_EnableIRQ(UART0_IRQn);
return RT_EOK;
}
static rt_err_t rt_uart_open(rt_device_t dev, rt_uint16_t oflag)
{
RT_ASSERT(dev != RT_NULL);
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
/* Enable the UART Interrupt */
NVIC_EnableIRQ(UART0_IRQn);
}
return RT_EOK;
}
static rt_err_t rt_uart_close(rt_device_t dev)
{
RT_ASSERT(dev != RT_NULL);
if (dev->flag & RT_DEVICE_FLAG_INT_RX)
{
/* Disable the UART Interrupt */
NVIC_DisableIRQ(UART0_IRQn);
}
return RT_EOK;
}
static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
{
rt_size_t length;
struct nrf51822_uart *uart = (struct nrf51822_uart*)dev;
/* interrupt receive */
rt_base_t level;
RT_ASSERT(uart != RT_NULL);
/* disable interrupt */
level = rt_hw_interrupt_disable();
length = rt_ringbuffer_get(&(uart->rx_rb), buffer, size);
/* enable interrupt */
rt_hw_interrupt_enable(level);
return length;
}
static rt_size_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
{
char *ptr;
ptr = (char*) buffer;
if (dev->open_flag & RT_DEVICE_FLAG_STREAM)
{
/* stream mode */
while (size)
{
if (*ptr == '\n')
{
NRF_UART0->TXD = (uint8_t)'\r';
// Wait for TXD data to be sent.
while (NRF_UART0->EVENTS_TXDRDY != 1) ;
NRF_UART0->EVENTS_TXDRDY = 0;
}
NRF_UART0->TXD = (uint8_t)(*ptr);
// Wait for TXD data to be sent.
while (NRF_UART0->EVENTS_TXDRDY != 1) ;
NRF_UART0->EVENTS_TXDRDY = 0;
ptr ++;
size --;
}
}
else
{
while ( size != 0 )
{
NRF_UART0->TXD = (uint8_t)(*ptr);
// Wait for TXD data to be sent.
while (NRF_UART0->EVENTS_TXDRDY != 1) ;
NRF_UART0->EVENTS_TXDRDY = 0;
ptr++;
size--;
}
}
return (rt_size_t) ptr - (rt_size_t) buffer;
}
void rt_hw_uart_init(void)
{
struct nrf51822_uart* uart;
/* get uart device */
uart = &uart_device;
/* device initialization */
uart->parent.type = RT_Device_Class_Char;
rt_ringbuffer_init(&(uart->rx_rb), rx_buffer, sizeof(rx_buffer));
/* device interface */
uart->parent.init = rt_uart_init;
uart->parent.open = rt_uart_open;
uart->parent.close = rt_uart_close;
uart->parent.read = rt_uart_read;
uart->parent.write = rt_uart_write;
uart->parent.control = RT_NULL;
uart->parent.user_data = RT_NULL;
rt_device_register(&uart->parent, "uart0", RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX);
}