STM32 RT-Thread OS实战

RT-Thread是一个国产实时操作系统。

使用的平台：秉火STM32 Cortex-M3内核开发板，RT-Thread v3.1.3。

RT-Thread移植

以秉火-指南者STM32F103VE6为例。参考官方文档，Git仓库，在keil5中添加RT-Thread内核，并下载源码：

git clone git@github.com:RT-Thread/rt-thread.git

用keil5打开rt-thread\bsp\stm32\stm32f103-fire-arbitrary\project.uvprojx，修改下载器配置，选择芯片STM32F103VE6，并修改main.c中的LED管脚，因为此例程使用的是STM32F103ZET6芯片版本。

/* defined the LED0 pin: PF7 */
//#define LED0_PIN    GET_PIN(F, 7)
#define LED0_PIN    GET_PIN(B, 0) //LED_G
#define LED1_PIN    GET_PIN(B, 1) //LED_B
#define LED2_PIN    GET_PIN(B, 5) //LED_R
int main(void)
{int count = 1;/* set LED0 pin mode to output */rt_pin_mode(LED0_PIN, PIN_MODE_OUTPUT);rt_pin_mode(LED1_PIN, PIN_MODE_OUTPUT);rt_pin_mode(LED2_PIN, PIN_MODE_OUTPUT);rt_pin_write(LED0_PIN, PIN_LOW);rt_pin_write(LED1_PIN, PIN_LOW);rt_pin_write(LED2_PIN, PIN_LOW);while (count++){rt_pin_write(LED0_PIN, PIN_LOW);//rt_kprintf("SET LOW\n");rt_thread_mdelay(100);rt_pin_write(LED0_PIN, PIN_HIGH);  //OFF ???!//rt_kprintf("SET HIGH\n");rt_thread_mdelay(100);rt_pin_write(LED1_PIN, PIN_LOW);rt_thread_mdelay(100);rt_pin_write(LED1_PIN, PIN_HIGH);rt_thread_mdelay(100);rt_pin_write(LED2_PIN, PIN_LOW);rt_thread_mdelay(100);rt_pin_write(LED2_PIN, PIN_HIGH);rt_thread_mdelay(100);}return RT_EOK;
}

值得注意的是，PIN_HIGH会使灯关闭，PIN_LOW会使灯关闭，这一点还没有搞清楚。在控制台输出使用rt_kprintf()函数，输出在UART串口，连接电脑即可显示。

RT-Thread Qemu仿真

参考QEMU-Ubuntu，图片访问有问题，建议下载仓库查看readme。

UART读取北斗数据

在STM32F103指南者上引脚如下，其中UART1为console串口，输出信息。

PIN NAME	PIN ADDR
UART1_RX	PIN A9
UART1_TX	PIN A10
UART3_RX	PIN B10
UART3_TX	PIN B11

连接北斗单元至UART3，在固件库版本中将UART1输出重定向为printf，将UART3输入重定向为scanf，这样就很轻松的读取到北斗的数据。同样的，在RT Thread版本中，在使用UART3之前首先需要定义设备和管脚，并打开：

//board.c
/*------------------------ UART3 CONFIG BEGIN -------------------------*/
#define BSP_USING_UART3
#define UART3_TX_PORT GPIOB
#define UART3_RX_PORT GPIOB
#define UART3_TX_PIN GPIO_PIN_10
#define UART3_RX_PIN GPIO_PIN_11
/*------------------------  UART3 CONFIG END  -------------------------*/

在main.c的路径下创建uart3.c文件，添加如下内容：

#include <rtthread.h>
#include <rtdevice.h>#define SAMPLE_UART_NAME "uart3"
static struct rt_semaphore rx_sem;
static rt_device_t serial;static rt_err_t uart_input(rt_device_t dev, rt_size_t size)
{rt_sem_release(&rx_sem);return RT_EOK;
}static void serial_thread_entry(void *parameter)
{char ch;while (1){while (rt_device_read(serial, -1, &ch, 1) != 1){rt_sem_take(&rx_sem, RT_WAITING_FOREVER);}rt_kprintf("%c", ch);ch = ch + 1;//rt_device_write(serial, 0, &ch, 1);}
}static int uart_sample(int argc, char *argv[])
{struct serial_configure config = RT_SERIAL_CONFIG_DEFAULT;config.baud_rate = BAUD_RATE_38400;config.data_bits = DATA_BITS_8;config.stop_bits = STOP_BITS_1;config.bufsz = 128;config.parity = PARITY_NONE;rt_err_t ret = RT_EOK;char uart_name[RT_NAME_MAX];char str[] = "hello RT-Thread!\r\n";if (argc == 2){rt_strncpy(uart_name, argv[1], RT_NAME_MAX);}else{rt_strncpy(uart_name, SAMPLE_UART_NAME, RT_NAME_MAX);}serial = rt_device_find(uart_name);if (!serial){rt_kprintf("find %s failed!\n", uart_name);return RT_ERROR;}rt_sem_init(&rx_sem, "rx_sem", 0, RT_IPC_FLAG_FIFO);rt_device_control(serial, RT_DEVICE_CTRL_CONFIG, &config);rt_device_open(serial, RT_DEVICE_FLAG_INT_RX);rt_device_set_rx_indicate(serial, uart_input);rt_device_write(serial, 0, str, (sizeof(str) - 1));rt_thread_t thread = rt_thread_create("serial", serial_thread_entry, RT_NULL, 1024, 25, 10);if (thread != RT_NULL){rt_thread_startup(thread);}else{ret = RT_ERROR;}return ret;
}MSH_CMD_EXPORT(uart_sample, uart device sample);

该文件中，最后一句完成看自定义命令的添加。完成以上配置后，下载后打开串口输入命令查看结果：

管脚中断

通过按键1和2改变灯的亮灭。这里主要使用了管脚输入输出和中断输入。

#include <rtthread.h>
#include <rtdevice.h>#define LED0_PIN_NUM 16  /* PB0  */
#define KEY0_PIN_NUM 0   /* PA0  */
#define KEY1_PIN_NUM 45  /* PC13 */void led_on(void *args)
{rt_kprintf("turn on led!\n");rt_pin_write(LED0_PIN_NUM, PIN_LOW);
}void led_off(void *args)
{rt_kprintf("turn off led!\n");rt_pin_write(LED0_PIN_NUM, PIN_HIGH);
}static void key_led_sample(void)
{rt_pin_mode(LED0_PIN_NUM, PIN_MODE_OUTPUT); rt_pin_write(LED0_PIN_NUM, PIN_LOW);rt_pin_mode(KEY0_PIN_NUM, PIN_MODE_INPUT_PULLUP); /* 绑定中断，下降沿模式，回调函数名为led_off */rt_pin_attach_irq(KEY0_PIN_NUM, PIN_IRQ_MODE_FALLING, led_on, RT_NULL);/* 使能中断 */rt_pin_irq_enable(KEY0_PIN_NUM, PIN_IRQ_ENABLE);rt_pin_mode(KEY1_PIN_NUM, PIN_MODE_INPUT_PULLUP);rt_pin_attach_irq(KEY1_PIN_NUM, PIN_IRQ_MODE_FALLING, led_off, RT_NULL);rt_pin_irq_enable(KEY1_PIN_NUM, PIN_IRQ_ENABLE);
}MSH_CMD_EXPORT(key_led_sample, key led sample);