串口发送一串报文驱动数码管显示内容一段时间后停止发送是什么环节出现了问题

大家好！想请教一下：我写了一个传感器采集数据，并打印和通过串口发送一串报文驱动数码管显示内容。采集的数据放在一个数组中。在测试中发现串口发送一段时间后就不再发送数据。想请教一下这是什么环节出现了问题。

1、传感器采集数据的程序

#include <SHT85.h>

#include <rtthread.h>

#include <rtdevice.h>

#include <board.h>

#include "sht3x.h"

#include <Usart.h>

#include <stdio.h>

#define SHT85_I2C_BUS_NAME "i2c1"

#define SHT85_ADDR 0x44

#define THREAD_PRIORITY 25

#define THREAD_STACK_SIZE 1024

#define THREAD_TIMESLICE 5

static rt_thread_t Sht85_Thread = RT_NULL;

static rt_thread_t Sht85_Print_Thread = RT_NULL;

static rt_sem_t Sht85_sem = RT_NULL;

float humidity = 0;

void SHT85_Init(void)

{

Sht85_sem = rt_sem_create("SHT85_sem", 0, RT_IPC_FLAG_FIFO);

//i2c1采集线程初始化 //

Sht85_Thread = rt_thread_create("SHT85_Get", SHT85_Thread_entry, RT_NULL, THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);

if(Sht85_Thread!=RT_NULL)

{

    rt_thread_startup(Sht85_Thread);

}

else {

    rt_kprintf("sht85 thread create failed\n");

}

Sht85_Print_Thread = rt_thread_create("SHT85_Print",SHT85_Print_Thread_entry,RT_NULL,THREAD_STACK_SIZE,THREAD_PRIORITY-1,THREAD_TIMESLICE);

if(Sht85_Print_Thread!=RT_NULL)

{

    rt_thread_startup(Sht85_Print_Thread);

}

}

static void SHT85_Thread_entry(void* parameter)

{

sht3x_device_t sht85_device;

sht85_device = sht3x_init(SHT85_I2C_BUS_NAME, SHT85_ADDR);

int i = 0;

while(1)

{

    if(sht3x_read_singleshot(sht85_device)==RT_EOK)

    {

        humidity = sht85_device->humidity;

        I2c1_Buffer[i++] = humidity;

        if(i==10)

        {

            rt_sem_release(Sht85_sem);

            i = 0;

        }

    }

    else {

        rt_kprintf("read sht85 fail.\r\n");

        break;

    }

    rt_thread_mdelay(200);

}

}

static void SHT85_Print_Thread_entry(void* parameter)

{

static rt_err_t sem_result;

while(1)

{

    sem_result = rt_sem_take(Sht85_sem, RT_WAITING_FOREVER);

    if(sem_result==RT_EOK)

    {

        printf("i2c1 value: %.2f\n",I2c1_Buffer[0]);

        uart6_transmit(I2c1_Buffer[0],0x02);

    }

    else {

        rt_sem_delete(Sht85_sem);

        return;

    }

    rt_thread_mdelay(2000);

}

}

2、串口发送的程序

#include <rtthread.h>

#include <Usart.h>

#include <rtdevice.h>

#include <math.h>

#define UART_NAME "uart6" /* 需要操作的设备 */

static rt_device_t serial; /* 设备句柄 */

struct serial_configure config = RT_SERIAL_CONFIG_DEFAULT;

void uart6_transmit(float x,uint8_t func) /*x为需要显示的变量（湿度、风速等），function为显示功能参数 */ //

{ //0x01--温度、0x02--湿度、0x03--风速、0x04--等效温度

rt_err_t ret = RT_EOK;

rt_size_t send_len = 0;

uint8_t PN;                                          //正负位//

uint8_t digits;                                      //小数点位//

Data_TypeDef num;

num.Frame_Head = 0xAA;

num.Length = 5;

num.Function = func;

if(x<0)

{

    PN = 0;

}

else {

    PN = 1;

}

if(x>=10 || (x<=-1&&x>-10))                                                //显示一位小数//

{

    digits = 1;

    if(x>0)

    {

        x = x*10;

    }

    else {

        x = -x*10;

    }

}

else if(x>-1 && x<10)                                                     //显示两位小数//

{

    digits = 2;

    if(x>0)

    {

        x = x*100;

    }

    else {

        x = -x*100;

    }

}

else if(x<=-10)                                                             //显示零位小数//

{

    digits = 0;

    x = -x;

}

num.Data_Nature = digits + PN*16;

num.Data_High = (int)x>>8;              //数据化为十六进制高八位//

num.Data_Low = (int)x & (0xFF);         //数据化为十六进制低八位//

num.BBC = num.Function^num.Data_High^num.Data_Low^num.Data_Nature;

uint8_t str[7] = {num.Frame_Head,num.Length,num.Function,num.Data_High,num.Data_Low,num.Data_Nature,num.BBC};

/* 查找系统中的串口设备 */

serial = rt_device_find(UART_NAME);

if (!serial)

{

    rt_kprintf("find %s failed!\n",UART_NAME);

}

/*配置参数*/

config.baud_rate = BAUD_RATE_9600;        //修改波特率为 9600

config.data_bits = DATA_BITS_8;           //数据位 8

config.stop_bits = STOP_BITS_1;           //停止位 1

config.bufsz     = 256;                   //修改缓冲区 buff size

config.parity    = PARITY_NONE;           //无奇偶校验位

rt_device_control(serial, RT_DEVICE_CTRL_CONFIG, &config);

/* 以中断接收及轮询发送模式打开串口设备 */

ret = rt_device_open(serial, RT_DEVICE_FLAG_INT_RX);

if (ret != RT_EOK)

{

    rt_kprintf("open device failed\r\n");

}

/* 发送字符串 */

send_len = rt_device_write(serial, 0, str, sizeof(str));

if (send_len != sizeof(str))

{

    rt_kprintf("send data failed\r\n");

}

///* 关闭设备 */

// ret = rt_device_close(serial);

// if (ret != RT_EOK)

// {

// rt_kprintf("close device failed\r\n");

// }

//

//// rt_kprintf("serial device test successful\r\n");

}

在串口调试助手捕获到这样的消息，是因为我的内存设置的原因吗？