uint32_t转double c代码

可以使用union或者memcpy来实现uint32_t到double的转换。

方法一：使用union

#include <stdio.h>
#include <stdint.h>

typedef union {
    uint32_t i;
    double d;
} uint32_double;

int main() {
    uint32_double ud;
    ud.i = 0x3f800000; // 1.0的uint32_t表示
    printf("%f\n", ud.d);
    return 0;
}

方法二：使用memcpy

#include <stdio.h>
#include <stdint.h>
#include <string.h>

int main() {
    uint32_t i = 0x3f800000; // 1.0的uint32_t表示
    double d;
    memcpy(&d, &i, sizeof(uint32_t));
    printf("%f\n", d);
    return 0;
}

两种方法都可以将uint32_t转换为double。注意在使用union时，需要确保uint32_t和double的大小相同。

相关问题

uint32_t ozone_oneCycleSample(void) { uint32_t sum=0,samples=100; uint16_t pre_adc_value,AD_value; int16_t diff; int16_t k; uint16_t adc_min,adc_max; double db_temp; while(TMR6!=100 && !i2c_rec_end); //if i2c recieved i2c data,quite synchronization //while(TMR6!=100); //if i2c recieved i2c data,quite synchronization cnt_10ms=0; pre_adc_value=0; //memset(&buff[0],0,1000); //GIE=0; adc_min=0xffff; adc_max=0; // LATA2=1; for(samples=0;cnt_10ms<2;) //for(samples_n=0;samples_n<1000;samples_n++) { AD_value=adc_oneSample(); diff=AD_value-pre_adc_value; if(diff>3 || diff<-3) { if(samples!=0) { sum+=pre_adc_value; samples++; } } else { sum+=AD_value; samples++; } pre_adc_value=AD_value; if(adc_max<AD_value)adc_max=AD_value; if(adc_min>AD_value)adc_min=AD_value; if(samples>250 && i2c_rec_end)break; } //rms // db_temp=adc_max-adc_min; // db_temp=db_temp*0.423; // sum=adc_min+db_temp; // samples=1; //mean if(samples==0)samples=1; sum=sum/samples; //GIE=1; // LATA2=0; return sum; }

这段代码是一个函数定义，名为`ozone_oneCycleSample`，返回一个无符号32位整数类型的值。

函数首先声明了一些变量，包括`sum`、`samples`、`pre_adc_value`、`AD_value`、`diff`、`k`、`adc_min`、`adc_max`和`db_temp`。

然后，在一个循环中，函数等待计时器TMR6的值为100，并且`i2c_rec_end`为假。这是为了在接收到I2C数据时，确保与I2C数据同步。

接下来，将变量`cnt_10ms`的值设置为0，将变量`pre_adc_value`的值设置为0。

然后，初始化变量`adc_min`为最大可能值0xffff，初始化变量`adc_max`为0。

接下来，进入一个循环，循环条件是在计时器TMR6的值小于100并且变量`cnt_10ms`小于2的情况下。在循环中，首先调用函数`adc_oneSample()`获取一个ADC采样值，并将其保存在变量`AD_value`中。

然后，计算变量`diff`的值，即当前采样值与上一次采样值之间的差异。

接下来，根据差异的大小判断是否需要将当前采样值加入到求和变量`sum`中。如果差异大于3或小于-3，则将上一次的采样值加入到`sum`中；否则，将当前的采样值加入到`sum`中。

每次更新完`sum`后，将当前采样值保存到`pre_adc_value`中，并更新最大值`adc_max`和最小值`adc_min`。

在循环中，如果`samples`大于250并且`i2c_rec_end`为真，则跳出循环。

接下来，计算均值。如果`samples`为0，则将`samples`设置为1，以避免除以0的错误。然后，将`sum`除以`samples`得到均值。

最后，返回均值`sum`作为函数的结果。

void button_handler(struct Button* handle) { uint8_t read_gpio_level = handle->hal_button_Level(handle->button_id); //ticks counter working.. if((handle->state) > 0) handle->ticks++; /*------------button debounce handle---------------*/ if(read_gpio_level != handle->button_level) { //not equal to prev one //continue read 3 times same new level change if(++(handle->debounce_cnt) >= DEBOUNCE_TICKS) { handle->button_level = read_gpio_level; handle->debounce_cnt = 0; } } else { //leved not change ,counter reset. handle->debounce_cnt = 0; } /*-----------------State machine-------------------*/ switch (handle->state) { case 0: if(handle->button_level == handle->active_level) { //start press down handle->event = (uint8_t)PRESS_DOWN; EVENT_CB(PRESS_DOWN); handle->ticks = 0; handle->repeat = 1; handle->state = 1; } else { handle->event = (uint8_t)NONE_PRESS; } break; case 1: if(handle->button_level != handle->active_level) { //released press up handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); handle->ticks = 0; handle->state = 2; } else if(handle->ticks > LONG_TICKS) { handle->event = (uint8_t)LONG_PRESS_START; EVENT_CB(LONG_PRESS_START); handle->state = 5; } break; case 2: if(handle->button_level == handle->active_level) { //press down again handle->event = (uint8_t)PRESS_DOWN; EVENT_CB(PRESS_DOWN); handle->repeat++; EVENT_CB(PRESS_REPEAT); // repeat hit handle->ticks = 0; handle->state = 3; } else if(handle->ticks > SHORT_TICKS) { //released timeout if(handle->repeat == 1) { handle->event = (uint8_t)SINGLE_CLICK; EVENT_CB(SINGLE_CLICK); } else if(handle->repeat == 2) { handle->event = (uint8_t)DOUBLe_CLICK; EVENT_CB(DOUBLe_CLICK); // repeat hit } handle->state = 0; } break; case 3: if(handle->button_level != handle->active_level) { //released press up handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); if(handle->ticks < SHORT_TICKS) { handle->ticks = 0; handle->state = 2; //repeat press } else { handle->state = 0; } }else if(handle->ticks > SHORT_TICKS){ // long press up handle->state = 0; } break; case 5: if(handle->button_level == handle->active_level) { //continue hold trigger handle->event = (uint8_t)LONG_PRESS_HOLD; EVENT_CB(LONG_PRESS_HOLD); } else { //releasd handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); handle->state = 0; //reset } break; default: handle->state = 0; //reset break; } }帮我详细注释这段代码

这段代码是一个按键处理函数，主要用于处理按键的状态和事件。下面是对代码的详细注释：

void button_handler(struct Button* handle) { 
    // 读取按键GPIO端口的电平值
    uint8_t read_gpio_level = handle->hal_button_Level(handle->button_id);   
    // 计数器开始工作
    if((handle->state) > 0) handle->ticks++; 

    /*------------按键消抖处理---------------*/
    if(read_gpio_level != handle->button_level) { //如果读到的电平值不同于之前的
        //连续读取3次相同的电平值
        if(++(handle->debounce_cnt) >= DEBOUNCE_TICKS) {
            handle->button_level = read_gpio_level; //更新电平值
            handle->debounce_cnt = 0; //重置消抖计数器
        }
    } else { //如果电平值没有变化，重置消抖计数器
        handle->debounce_cnt = 0;
    }

    /*-----------------状态机处理-------------------*/
    switch (handle->state) {
    case 0: //初始状态
        if(handle->button_level == handle->active_level) { //按键按下
            handle->event = (uint8_t)PRESS_DOWN; //设置按键事件
            EVENT_CB(PRESS_DOWN); //触发事件回调函数
            handle->ticks = 0; //重置计数器
            handle->repeat = 1; //重置按键重复次数
            handle->state = 1; //进入下一个状态
        } else {
            handle->event = (uint8_t)NONE_PRESS; //没有按键按下
        }
        break;

    case 1: //按键按下状态
        if(handle->button_level != handle->active_level) { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            handle->ticks = 0; //重置计数器
            handle->state = 2; //进入下一个状态
        } else if(handle->ticks > LONG_TICKS) { //按键按下超过长按时间
            handle->event = (uint8_t)LONG_PRESS_START; //设置按键事件
            EVENT_CB(LONG_PRESS_START); //触发事件回调函数
            handle->state = 5; //进入下一个状态
        }
        break;

    case 2: //单次按键按下后的状态
        if(handle->button_level == handle->active_level) { //按键再次按下
            handle->event = (uint8_t)PRESS_DOWN; //设置按键事件
            EVENT_CB(PRESS_DOWN); //触发事件回调函数
            handle->repeat++; //增加按键重复次数
            EVENT_CB(PRESS_REPEAT); //触发按键重复事件回调函数
            handle->ticks = 0; //重置计数器
            handle->state = 3; //进入下一个状态
        } else if(handle->ticks > SHORT_TICKS) { //按键松开超过短按时间
            if(handle->repeat == 1) { //单击事件
                handle->event = (uint8_t)SINGLE_CLICK; //设置按键事件
                EVENT_CB(SINGLE_CLICK); //触发事件回调函数
            } else if(handle->repeat == 2) { //双击事件
                handle->event = (uint8_t)DOUBLE_CLICK; //设置按键事件
                EVENT_CB(DOUBLE_CLICK); //触发事件回调函数
            }
            handle->state = 0; //回到初始状态
        }
        break;

    case 3: //按键重复状态
        if(handle->button_level != handle->active_level) { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            if(handle->ticks < SHORT_TICKS) { //按键松开时间小于短按时间
                handle->ticks = 0; //重置计数器
                handle->state = 2; //回到单次按键按下后的状态
            } else { //按键松开时间大于等于短按时间
                handle->state = 0; //回到初始状态
            }
        } else if(handle->ticks > SHORT_TICKS){ //按键按下时间大于短按时间
            handle->state = 0; //回到初始状态
        }
        break;

    case 5: //长按状态
        if(handle->button_level == handle->active_level) { //按键继续按下
            handle->event = (uint8_t)LONG_PRESS_HOLD; //设置按键事件
            EVENT_CB(LONG_PRESS_HOLD); //触发事件回调函数
        } else { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            handle->state = 0; //回到初始状态
        }
        break;

    default: //其他状态，回到初始状态
        handle->state = 0;
        break;
    }
}