求助，函数没写到主函数里，为什么能执行成功

只看该作者 · 2021-2-7 14:46

void SMG_Play()该函数没写到主函数里，但是一个错误和警告都没有，而且该函数还执行成功了？为什么？？求助

#include <STC15F2K60S2.H>
#include <onewire.h>

unsigned char code SMG_Select_1[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,0xbf,0x7f};
unsigned int temp=0;
unsigned char c=0;
unsigned char b=0;

void SMG_Play();

void SCQ_Set(unsigned char a)
{
switch(a)
{
case 4:P2=(P2&0x1f)|0x80;
   break;
case 5:P2=(P2&0x1f)|0xa0;
   break;
case 6:P2=(P2&0x1f)|0xc0;
   break;
case 7:P2=(P2&0x1f)|0xe0;
   break;
case 0:P2=(P2&0x1f)|0x00;
   break;
}
}

void Delay_1(unsigned int t)
{
while(t--);
}

void Delay_SMG(unsigned int t)
{
while(t--)
{
SMG_Play();
}
}

void SMG_Set(unsigned char num,unsigned char loc)
{
SCQ_Set(6);
P0=0x01<<loc;
SCQ_Set(7);
P0=num;
}

void DS18B20_Set()       //设置温度传感器
{
unsigned char MSB;
unsigned char LSB;

init_ds18b20();
Write_DS18B20(0xcc);
Write_DS18B20(0x44);
Delay_SMG(200);

init_ds18b20();
Write_DS18B20(0xcc);
Write_DS18B20(0xbe);
Delay_SMG(200);

LSB=Read_DS18B20();
MSB=Read_DS18B20();

temp=MSB<<4;
temp |=(LSB>>4);
}

void SMG_Play()
{

SMG_Set(SMG_Select_1[16],0);
Delay_1(100);P0=0xff;
SMG_Set(SMG_Select_1[0],1);
Delay_1(100);P0=0xff;
SMG_Set(SMG_Select_1[16],2);
Delay_1(100);P0=0xff;
SMG_Set(0xff,3);
Delay_1(100);P0=0xff;
SMG_Set(0xff,4);
Delay_1(100);P0=0xff;
SMG_Set(0xff,5);
Delay_1(100);P0=0xff;
SMG_Set(SMG_Select_1[temp/10],6);
Delay_1(100);P0=0xff;
SMG_Set(SMG_Select_1[temp%10],7);
Delay_1(100);P0=0xff;

}

void main()
{
P2=0x80;P0=0xff;
P2=0xa0;P0=0x00; //初始化
while(1)
{
DS18B20_Set();
}
}