博科园AI人工智能助手
图灵
1. 太阳直射北半球时，除极昼极夜的地区，全球其他地方太阳都是东北升西北落。（极昼地区太阳正北升正北落,正午太阳总在正南）
2.太阳直射南半球时，除极昼极夜的地区，全球其他地方太阳都是东南升西南落。（极昼地区太阳正南升正南落，正午太阳总在正北）。
3.太阳直射赤道时：晨线和经线重合，纬线和太阳光线平行，太阳在晨线正东方，在昏线的正西方，故太阳正东升，正西落。
在北半球，昼越长，日出越早，日落越晚，日出日落的位置越偏北，太阳视运动的弧度越大；反之，在北半球昼越短，日出越晚，日落越早，日出日落位置越偏南，太阳视运动的弧度越小。
正午太阳方位
1.太阳直射点位于观测者以南时，该地正午太阳位于正南方向。
2.太阳直射点位于观测者以北时，该地正午太阳位于正北方向。
![[s-70]](https://www.bokeyuan.net/pic/image/emoji/cas/70.png)
![#include <reg51.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <intrins.h>
#include <absacc.h>
sbit LED = P1^0;
sbit BUZZ = P1^1;
#define FREQ_MAX 2000 // 最大频率
#define FREQ_MIN 200 // 最小频率
#define SAMPLE_SIZE 128 // 采样点数
#define SAMPLE_RATE 8000 // 采样率
unsigned char code frequenceTable[7][7] = {
{0x8e,0x8a,0x8c,0x8d,0x87,0x89,0x8B}, // 1
{0x0e,0x0a,0x0c,0x0d,0x07,0x09,0x0B}, // 2
{0x26,0x22,0x24,0x25,0x1f,0x21,0x23}, // 3
{0x46,0x42,0x44,0x45,0x3f,0x41,0x43}, // 4
{0x66,0x62,0x64,0x65,0x5f,0x61,0x63}, // 5
{0x86,0x82,0x84,0x85,0x7f,0x81,0x83}, // 6
{0xa6,0xa2,0xa4,0xa5,0x9f,0xa1,0xa3} // 7
};
unsigned char sampleBuffer[SAMPLE_SIZE]; // 存储采样数据的缓冲区
void delay(unsigned int n)
{
unsigned int i, j;
for(i=0;i<n;i++)
for(j=0;j<60;j++);
}
void initTimer()
{
T2CON = 0x00; // 关闭定时器2
AUXR = AUXR & 0x7F; // 定时器2时钟由Fosc/12提升为Fosc/4
TH2 = 0xFF; // 计数器重载值
TL2 = 0xDC;
IE2 = IE2 & 0xFB; // 关闭定时器2中断
T2CON = T2CON | 0x04; // 打开定时器2
}
void startADC()
{
P2 = 0xff;
ADC_CONTR = ADC_POWER | ADC_SPEED(7) | ADC_FLAG;
_nop_();
_nop_();
_nop_();
_nop_();
ADC_CONTR = ADC_CONTR | ADC_START;
}
void stopADC()
{
ADC_CONTR = ADC_POWER;
}
void ADCConvert()
{
if(ADC_CONTR & ADC_FLAG)
{
ADC_CONTR = ADC_CONTR & 0x1f;
ADC_CONTR = ADC_CONTR | ADC_START;
sampleBuffer[sampleIndex++] = ADC_RES;
}
}
void FFT(unsigned char *x, unsigned int N)
{
unsigned int i, j, k, n1, n2, a;
unsigned char xt_r, xt_i, yt_r, yt_i;
double c, s;
j = 0;
for(i=0; i<N-1; i++)
{
if(i < j)
{
xt_r = x[2*i];
xt_i = x[2*i+1];
x[2*i] = x[2*j];
x[2*i+1] = x[2*j+1];
x[2*j] = xt_r;
x[2*j+1] = xt_i;
}
k = N / 2;
while(k <= j)
{
j = j - k;
k = k / 2;
}
j = j + k;
}
n1 = 2;
for (i=0; i<N; i+=2)
{
n2 = n1;
n1 = n1 << 1;
c = 1.0;
s = 0.0;
a = 0;
for(j=0; j<n2; j+=2)
{
for(k=i+j; k<N; k+=n1)
{
xt_r = x[2*(k+n2)];
xt_i = x[2*(k+n2)+1];
yt_r = (unsigned char)(c * xt_r - s * xt_i);
yt_i = (unsigned char)(c * xt_i + s * xt_r);
x[2*(k+n2)] = x[2*k] - yt_r;
x[2*(k+n2)+1] = x[2*k+1] - yt_i;
x[2*k] = x[2*k] + yt_r;
x[2*k+1] = x[2*k+1] + yt_i;
}
a += (N/2);
c = cos(2 * M_PI * a / N);
s = 0 - sin(2 * M_PI * a / N);
}
}
}
unsigned char getMaxFrequency(unsigned char *x, unsigned int N, unsigned int sampleRate)
{
unsigned int i, maxIndex;
unsigned char maxValue;
unsigned int freq;
FFT(x, N);
maxIndex = 0;
maxValue = x[0];
for(i=1; i<N/2; i++)
{
if(x[2*i] > maxValue)
{
maxIndex = i;
maxValue = x[2*i];
}
}
freq = maxIndex * sampleRate / N;
return freq;
}
void displayFrequency(unsigned int freq)
{
unsigned char code dispNumber[10] = {0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F};
unsigned char digit1, digit2;
digit1 = freq / 10;
digit2 = freq % 10;
P0 = ~(0x01);
P2 = dispNumber[digit1];
delay(2);
P0 = ~(0x02);
P2 = dispNumber[digit2];
delay(2);
P0 = 0xff;
}
void main()
{
unsigned int sampleIndex = 0;
BUZZ = 0;
initTimer();
startADC();
while(1)
{
ADCConvert();
if(sampleIndex >= SAMPLE_SIZE)
{
stopADC();
unsigned int freq = getMaxFrequency(sampleBuffer, SAMPLE_SIZE, SAMPLE_RATE);
displayFrequency(freq);
sampleIndex = 0;
startADC();
}
}
}
给我在每一条代码后加上明确的注释，每一条代码都需要](https://pic.bokeyuan.net/image/liwu/%E6%A3%92%E6%A3%92%E7%B3%96.jpg)
![[s-7]](https://www.bokeyuan.net/pic/image/emoji/cas/7.png)
![[s-20]](https://www.bokeyuan.net/pic/image/emoji/cas/20.png)
