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의뢰는 http://instructables.tistory.com/64로 남겨주세요

https://electrosome.com/hc-sr04-ultrasonic-sensor-pic/

HC-SR04는 4핀짜리 Ultra Sonic Sensor이다.

여기서는 MikroC로 짠 코드와 MPLAB으로 짠 코드를 비교할 것이다.

MPLAB-XC8.zip

▼Proteus ISIS 추가용 라이브러리 (HC-SR04) (☞출처)

Ultrasonic Sensor Library for Proteus.rar

▼Proteus ISIS용 HC-SR04 ---PIC칩용 (☞출처)

ultrasound.rar

▼Proteus, Hyperterminal & Virtual Port

https://www.youtube.com/watch?v=gwkju6f2Twk

▼Google에서 Virtual Port Emulator라고 검색

http://www.eterlogic.com/Products.VSPE.html

SetupVSPE.zip

▼MikroC

// LCD module connections
sbit LCD_RS at RD2_bit;
sbit LCD_EN at RD3_bit;
sbit LCD_D4 at RD4_bit;
sbit LCD_D5 at RD5_bit;
sbit LCD_D6 at RD6_bit;
sbit LCD_D7 at RD7_bit;

sbit LCD_RS_Direction at TRISD2_bit;
sbit LCD_EN_Direction at TRISD3_bit;
sbit LCD_D4_Direction at TRISD4_bit;
sbit LCD_D5_Direction at TRISD5_bit;
sbit LCD_D6_Direction at TRISD6_bit;
sbit LCD_D7_Direction at TRISD7_bit;
// End LCD module connections

void main()
{
  int a;
  char txt[7];
  Lcd_Init();
  Lcd_Cmd(_LCD_CLEAR);          // Clear display
  Lcd_Cmd(_LCD_CURSOR_OFF);     // Cursor off

  TRISB = 0b00010000;           //RB4 as Input PIN (ECHO)

  Lcd_Out(1,1,"Developed By");
  Lcd_Out(2,1,"electroSome");

  Delay_ms(3000);
  Lcd_Cmd(_LCD_CLEAR);

  T1CON = 0x10;                 //Initialize Timer Module

  while(1)
  {
    TMR1H = 0;                  //Sets the Initial Value of Timer
    TMR1L = 0;                  //Sets the Initial Value of Timer

    PORTB.F0 = 1;               //TRIGGER HIGH
    Delay_us(10);               //10uS Delay
    PORTB.F0 = 0;               //TRIGGER LOW

    while(!PORTB.F4);           //Waiting for Echo
    T1CON.F0 = 1;               //Timer Starts
    while(PORTB.F4);            //Waiting for Echo goes LOW
    T1CON.F0 = 0;               //Timer Stops

    a = (TMR1L | (TMR1H<<8));   //Reads Timer Value
    a = a/58.82;                //Converts Time to Distance
    a = a + 1;                  //Distance Calibration\
    if(a>=2 && a<=400)          //Check whether the result is valid or not
    {
      IntToStr(a,txt);
      Ltrim(txt);
      Lcd_Cmd(_LCD_CLEAR);
      Lcd_Out(1,1,"Distance = ");
      Lcd_Out(1,12,txt);
      Lcd_Out(1,15,"cm");
    }
    else
    {
      Lcd_Cmd(_LCD_CLEAR);
      Lcd_Out(1,1,"Out of Range");
    }
    Delay_ms(400);
  }
}

▼MPLAB XC8

#define _XTAL_FREQ 8000000

#define RS RD2
#define EN RD3
#define D4 RD4
#define D5 RD5
#define D6 RD6
#define D7 RD7

#include <xc.h>
#include "lcd.h";
#include <pic16f877a.h>

// BEGIN CONFIG
#pragma config FOSC = HS   
#pragma config WDTE = OFF  
#pragma config PWRTE = OFF 
#pragma config BOREN = ON 
#pragma config LVP = OFF   
#pragma config CPD = OFF   
#pragma config WRT = OFF  
#pragma config CP = OFF    
//END CONFIG
void main()
{ 
  int a;

  TRISB = 0b00010000;         //RB4 as Input PIN (ECHO)
  TRISD = 0x00;               // LCD Pins as Output

  Lcd_Init();

  Lcd_Set_Cursor(1,1);
  Lcd_Write_String("Developed By");
  Lcd_Set_Cursor(2,1);
  Lcd_Write_String("electroSome");

  __delay_ms(3000);
  Lcd_Clear();

  T1CON = 0x10;               //Initialize Timer Module

  while(1)
  { 
    TMR1H = 0;                //Sets the Initial Value of Timer
    TMR1L = 0;                //Sets the Initial Value of Timer

    RB0 = 1;                  //TRIGGER HIGH
    __delay_us(10);           //10uS Delay 
    RB0 = 0;                  //TRIGGER LOW

    while(!RB4);              //Waiting for Echo
    TMR1ON = 1;               //Timer Starts
    while(RB4);               //Waiting for Echo goes LOW
    TMR1ON = 0;               //Timer Stops

    a = (TMR1L | (TMR1H<<8)); //Reads Timer Value
    a = a/58.82;              //Converts Time to Distance
    a = a + 1;                //Distance Calibration
    if(a>=2 && a<=400)        //Check whether the result is valid or not
    { 
      Lcd_Clear();
      Lcd_Set_Cursor(1,1);
      Lcd_Write_String("Distance = ");

      Lcd_Set_Cursor(1,14);
      Lcd_Write_Char(a%10 + 48);

      a = a/10;
      Lcd_Set_Cursor(1,13);
      Lcd_Write_Char(a%10 + 48);

      a = a/10;
      Lcd_Set_Cursor(1,12);
      Lcd_Write_Char(a%10 + 48);

      Lcd_Set_Cursor(1,15);
      Lcd_Write_String("cm");
    }  
    else
    {
      Lcd_Clear();
      Lcd_Set_Cursor(1,1);
      Lcd_Write_String("Out of Range");
    }
    __delay_ms(400);
  }
}

-----------------------------------------------------------------------------------------

-----------------------------------------------------------------------------------------

I hope that you can understand the working of the above program through comments. 

If you have any doubts, just comment below.

Distance Calibration

For accurate distance measuring you may calibrate the obtained result. Here for making the displayed distance more accurate, I added 1 to the the measured distance. This constant of calibration can be find using a series of practical experiments with a ruler scale.

In the above program there is a small problem as it infinitely waiting for ECHO and to ECHO goes LOW. If HIGH echo pulse is not received due to any reason, the program may get stuck there. So it is not a good practice to infinitely wait for ECHO and to ECHO goes LOW.  The best solution is to use PORTB On-Change Interrupt feature of PIC Microcontroller.

PORTB On-Change Interrupt

Four pins of PORTB (RB4 – RB7) have interrupt on-change feature.

포트B(RB4~RB7) 는 인터럽트 on-change 특성을 갖고있다.

Only those pins configured as INPUT PIN can cause this Interrupt while this interrupt is enabled.

이런 입력핀들만이 인터럽트를 유발할 수 있다. while 이 인터럽트가 enabled된 동안에

If the Logic State of any of these four pin changes (only Input Pins), interrupt will be generated.

만약 이 4개핀(PB4~PB7)이 바뀌었으면, 인터럽트가 발생할 것이다.

PORTB On-Change Interrupt can be enabled by :

• Set Global Interrupt Enable bit : INTCON.GIE = 1
• Set PORTB On-Change Interrupt Enable Bit : INTCON.RBIE = 1

다음 조건하에 PortB의 On-Change 인터럽트는 인에이블될수 있다.

● INTCON안의 GIE비트가 1로 Set됬을때

● INTCON안의 RBIE비트가 1로 Set됬을때

Note : PORTB On-Change Interrupt flag (INTCON.RBIF) will be set whenever this interrupt is generated and it should be cleared in software

이제 인터럽트가 추가된 코드를 보자

▼MikroC (Interrupt Used)

// LCD module connections
sbit LCD_RS at RD2_bit;
sbit LCD_EN at RD3_bit;
sbit LCD_D4 at RD4_bit;
sbit LCD_D5 at RD5_bit;
sbit LCD_D6 at RD6_bit;
sbit LCD_D7 at RD7_bit;

sbit LCD_RS_Direction at TRISD2_bit;
sbit LCD_EN_Direction at TRISD3_bit;
sbit LCD_D4_Direction at TRISD4_bit;
sbit LCD_D5_Direction at TRISD5_bit;
sbit LCD_D6_Direction at TRISD6_bit;
sbit LCD_D7_Direction at TRISD7_bit;
// End LCD module connections

int a;

//Interrupt function will be automatically executed on Interrupt
void interrupt() 
{
  if(INTCON.RBIF == 1)                 //Makes sure that it is PORTB On-Change Interrupt
  {
    INTCON.RBIE = 0;                   //Disable On-Change Interrupt
    if(PORTB.F4 == 1)                  //If ECHO is HIGH
      T1CON.F0 = 1;                    //Start Timer
    if(PORTB.F4 == 0)                  //If ECHO is LOW
    {
      T1CON.F0 = 0;                    //Stop Timer
      a = (TMR1L | (TMR1H<<8))/58.82;  //Calculate Distance
    }
  }
  INTCON.RBIF = 0;                     //Clear PORTB On-Change Interrupt flag
  INTCON.RBIE = 1;                     //Enable PORTB On-Change Interrupt
}
 
void main()
{
  char txt[7];
  Lcd_Init();
  Lcd_Cmd(_LCD_CLEAR);                 // Clear display
  Lcd_Cmd(_LCD_CURSOR_OFF);            // Cursor off

  TRISB = 0b00010000;
  INTCON.GIE = 1;                      //Global Interrupt Enable
  INTCON.RBIF = 0;                     //Clear PORTB On-Change Interrupt Flag
  INTCON.RBIE = 1;                     //Enable PORTB On-Change Interrupt

  Lcd_Out(1,1,"Developed By");
  Lcd_Out(2,1,"electroSome");

  Delay_ms(3000);
  Lcd_Cmd(_LCD_CLEAR);

  T1CON = 0x10;                        //Initializing Timer Module

  while(1)
  { 
    TMR1H = 0;                         //Setting Initial Value of Timer
    TMR1L = 0;                         //Setting Initial Value of Timer

    a = 0;

    PORTB.F0 = 1;                      //TRIGGER HIGH
    Delay_us(10);                      //10uS Delay
    PORTB.F0 = 0;                      //TRIGGER LOW

    Delay_ms(100);                     //Waiting for ECHO
    a = a + 1;                         //Error Correction Constant
    if(a>2 && a<400)                   //Check whether the result is valid or not
    {
      IntToStr(a,txt);
      Ltrim(txt);
      Lcd_Cmd(_LCD_CLEAR);
      Lcd_Out(1,1,"Distance = ");
      Lcd_Out(1,12,txt);
      Lcd_Out(1,15,"cm");
    }
    else
    {
      Lcd_Cmd(_LCD_CLEAR);
      Lcd_Out(1,1,"Out of Range");
    }
    Delay_ms(400);
  }
}

▼MPLAB XC8 (Interrupt Used)

#define _XTAL_FREQ 8000000

#define RS RD2
#define EN RD3
#define D4 RD4
#define D5 RD5
#define D6 RD6
#define D7 RD7

#include <xc.h>
#include "lcd.h";
#include <pic16f877a.h>

// BEGIN CONFIG
#pragma config FOSC = HS 
#pragma config WDTE = OFF
#pragma config PWRTE = OFF
#pragma config BOREN = ON 
#pragma config LVP = OFF 
#pragma config CPD = OFF 
#pragma config WRT = OFF 
#pragma config CP = OFF
//END CONFIG

int a;

void interrupt echo()
{
  if(RBIF == 1)                       //Makes sure that it is PORTB On-Change Interrupt
  {
    RBIE = 0;                         //Disable On-Change Interrupt
    if(RB4 == 1)                      //If ECHO is HIGH
    TMR1ON = 1;                       //Start Timer
    if(RB4 == 0)                      //If ECHO is LOW
    {
      TMR1ON = 0;                     //Stop Timer
      a = (TMR1L | (TMR1H<<8))/58.82; //Calculate Distance
    }
  }
  RBIF = 0;                           //Clear PORTB On-Change Interrupt flag
  RBIE = 1;                           //Enable PORTB On-Change Interrupt
}
void main()
{
  TRISB = 0b00010000;                 //RB4 as Input PIN (ECHO)
  TRISD = 0x00;                       // LCD Pins as Output
  GIE = 1;                            //Global Interrupt Enable
  RBIF = 0;                           //Clear PORTB On-Change Interrupt Flag
  RBIE = 1;                           //Enable PORTB On-Change Interrupt

  Lcd_Init();

  Lcd_Set_Cursor(1,1);
  Lcd_Write_String("Developed By");
  Lcd_Set_Cursor(2,1);
  Lcd_Write_String("electroSome");

  __delay_ms(3000);
  Lcd_Clear();

  T1CON = 0x10;                       //Initialize Timer Module

  while(1)
  {
    TMR1H = 0;                        //Sets the Initial Value of Timer
    TMR1L = 0;                        //Sets the Initial Value of Timer

    RB0 = 1;                          //TRIGGER HIGH
    __delay_us(10);                   //10uS Delay
    RB0 = 0;                          //TRIGGER LOW 

    __delay_ms(100);                  //Waiting for ECHO
    a = a + 1;                        //Error Correction Constant

    if(a>=2 && a<=400)                //Check whether the result is valid or not
    {
      Lcd_Clear();
      Lcd_Set_Cursor(1,1);
      Lcd_Write_String("Distance = ");

      Lcd_Set_Cursor(1,14);
      Lcd_Write_Char(a%10 + 48);

      a = a/10;
      Lcd_Set_Cursor(1,13);
      Lcd_Write_Char(a%10 + 48);

      a = a/10;
      Lcd_Set_Cursor(1,12);
      Lcd_Write_Char(a%10 + 48);

      Lcd_Set_Cursor(1,15);
      Lcd_Write_String("cm");
    }
    else
    {
      Lcd_Clear();
      Lcd_Set_Cursor(1,1);
      Lcd_Write_String("Out of Range");
    }
    __delay_ms(400);
  }
}

--------------------------------------------------------------------------------------

---------------------------------------------------------------------------------------

http://waihung.net/hc-sr04-ultrasonic-sensor-on-pic/

▲ PIC16F877A, HC-SR04, LCD16x2, MPLAB X(MPLAB IDE를 사용해도 무방하다)

▲Hi-Tech C compiler (하이텍 C 컴파일러)

HI-TECH_PICC_PRO_9.71a (Activate하는법).zip

▼좀더 많은 칩을 지원해준다. (9.71a 압축을 풀어보고 사용하려는 칩을 지원해주지 않느다면 아래것을 받도록 하자.)

picc-9_82-win.vol1.egg

picc-9_82-win.vol2.egg

PIC16F877A_Ultrasonic_LCD.rar

Main코드는 아래와 같다. (나머지는 파일을 받으면 된다.)

#include <stdio.h>
#include <stdlib.h>
#include <pic.h>
#include <htc.h>
#define _XTAL_FREQ 16e6
__CONFIG(WDTE_OFF & CP_OFF & FOSC_HS & PWRTE_ON & LVP_OFF);


#define RS RB2
#define EN RB3
#define D4 RB4
#define D5 RB5
#define D6 RB6
#define D7 RB7

#include "lcd.h"

#define _XTAL_FREQ 16e6

// Lcd4_Init(); Lcd4_Clear() Lcd4_Set_Cursor() : Lcd4_Write_Char() Lcd4_Write_String()

unsigned int distance = 0;
char lcd_distance[10];

void sendPulse(void);
unsigned int readUltrasonic(void);

int main(int argc, char** argv) {
    TRISB = 0;
    RB0 = 0;
    TRISD = 0xFF;
    OPTION_REG &= 0b11000110;
    Lcd4_Init();

    Lcd4_Set_Cursor(1,0);
    Lcd4_Write_String("Ultrasonic");

    while(1) {
        distance = readUltrasonic()/1.7;

        sprintf(lcd_distance,"%d",distance);
        Lcd4_Set_Cursor(2,0);
        Lcd4_Write_String(lcd_distance);

        //Lcd4_Set_Cursor(2,6);
        Lcd4_Write_String(" cm     ");

        __delay_ms(300);

    }

    return (EXIT_SUCCESS);
}

void sendPulse(void) {
    RB0 = 1;
    __delay_us(10);
    RB0 = 0;
}

unsigned int readUltrasonic(void){
    unsigned int time = 0;
    

    while(1) { if(RD0==0) { break; } }

    sendPulse();
    while(1) {
        if(RD0==1)
        {
            TMR0 = 0;
            while(1)
            {
                if(RD0==0){
                    time = TMR0;
                    return time;
                }
            }
        }
    }

}

---------------------------------------------------------------------------------------

https://electrosome.com/blinking-led-pic-microcontroller-hi-tech-c/

추가로 Hi-Tech 기본코드는 아래와 같다.

#include <htc.h>
#define _XTAL_FREQ 8000000
void main()
{
  TRISB=0X00;
  PORTB=0X00;
  while(1)
  { 
    PORTB=0XFF;
    __delay_ms(1000);
    PORTB=0X00;
    __delay_ms(1000);
  }
}

http://www.instructables.com/id/How-to-Program-a-PIC-Microcontroller-Read-an-Encod/?ALLSTEPS

Encoder(인코더)를 돌렸을때 PIC18F4520에서 발생하는 출력값을 Oscillocope로 측적하는 실험을 하겠다.

MPLAB X IDE

Select Compiler: XC8

Chip : PIC18F4520

Encoder (Pololu Item # 2269)

출처 https://www.pololu.com/product/2269

▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼

/********************************************************************

How to program a PIC & read an encoder program

Last Revised: 1/3/14
Authors: Carson Miller
Written for: PIC18F4525 (Current Version)

*********************************************************************/

#define INPUT         1
#define OUTPUT     0

#define _XTAL_FREQ 4000000  //Used by the XC8 delay_ms(x) macro

// PIC18F25K22 Configuration Bit Settings

#include <xc.h>                             //Includes PIC hardware mapping
#include "GenericTypeDefs.h"      //Includes standard variable types
                                            //XC8 내에 기본적으로 제공해주는 Header이다.

// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.

// CONFIG1H
#pragma config OSC = INTIO7 

// Oscillator Selection bits (Internal oscillator block, CLKOUT function on RA6, port function on RA7)

//내부 오실레이터 선택비트

#pragma config FCMEN = OFF 

// Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)

#pragma config IESO = OFF 

// Internal/External Oscillator Switchover bit (Oscillator Switchover mode disabled)

// CONFIG2L
#pragma config PWRT = OFF // Power-up Timer Enable bit (PWRT disabled)
#pragma config BOREN = SBORDIS // Brown-out Reset Enable bits (Brown-out Reset enabled in hardware only (SBOREN is disabled))
#pragma config BORV = 3 // Brown Out Reset Voltage bits (Minimum setting)

// CONFIG2H
#pragma config WDT = OFF // Watchdog Timer Enable bit (WDT enabled)
#pragma config WDTPS = 32768 // Watchdog Timer Postscale Select bits (1:32768)

// CONFIG3H
#pragma config CCP2MX = PORTC // CCP2 MUX bit (CCP2 input/output is multiplexed with RC1)
#pragma config PBADEN = ON // PORTB A/D Enable bit (PORTB<4:0> pins are configured as analog input channels on Reset)
#pragma config LPT1OSC = OFF // Low-Power Timer1 Oscillator Enable bit (Timer1 configured for higher power operation)
#pragma config MCLRE = ON // MCLR Pin Enable bit (MCLR pin enabled; RE3 input pin disabled)

// CONFIG4L
#pragma config STVREN = ON // Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
#pragma config LVP = OFF // Single-Supply ICSP Enable bit (Single-Supply ICSP enabled)
#pragma config XINST = OFF // Extended Instruction Set Enable bit (Instruction set extension and Indexed Addressing mode disabled (Legacy mode))

// CONFIG5L
#pragma config CP0 = OFF // Code Protection bit (Block 0 (000800-003FFFh) not code-protected)
#pragma config CP1 = OFF // Code Protection bit (Block 1 (004000-007FFFh) not code-protected)
#pragma config CP2 = OFF // Code Protection bit (Block 2 (008000-00BFFFh) not code-protected)

// CONFIG5H
#pragma config CPB = OFF // Boot Block Code Protection bit (Boot block (000000-0007FFh) not code-protected)
#pragma config CPD = OFF // Data EEPROM Code Protection bit (Data EEPROM not code-protected)

// CONFIG6L
#pragma config WRT0 = OFF // Write Protection bit (Block 0 (000800-003FFFh) not write-protected)
#pragma config WRT1 = OFF // Write Protection bit (Block 1 (004000-007FFFh) not write-protected)
#pragma config WRT2 = OFF // Write Protection bit (Block 2 (008000-00BFFFh) not write-protected)

// CONFIG6H
#pragma config WRTC = OFF // Configuration Register Write Protection bit (Configuration registers (300000-3000FFh) not write-protected)
#pragma config WRTB = OFF // Boot Block Write Protection bit (Boot Block (000000-0007FFh) not write-protected)
#pragma config WRTD = OFF // Data EEPROM Write Protection bit (Data EEPROM not write-protected)

// CONFIG7L
#pragma config EBTR0 = OFF // Table Read Protection bit (Block 0 (000800-003FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR1 = OFF // Table Read Protection bit (Block 1 (004000-007FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR2 = OFF // Table Read Protection bit (Block 2 (008000-00BFFFh) not protected from table reads executed in other blocks)

// CONFIG7H
#pragma config EBTRB = OFF // Boot Block Table Read Protection bit (Boot Block (000000-0007FFh) not protected from table reads executed in other blocks)

//Dummy variable setup

UINT distance = 0;
CHAR direction = 0;
CHAR error = 0;

void configure(void)
{

//ADC Setup

ADCON1bits.PCFG = 1111; //Turns off all analog inputs (See datasheet p. 224)

//Oscillator Setup

OSCCONbits.IRCF = 110; //Sets oscillator to 4MHz

//Interrupt Setup

INTCONbits.GIE = 1; //Enables all unmasked or high priority interrupts (Depending on IPEN)
INTCONbits.PEIE = 1; //Enables all unmasked peripheral interrupts or low- priority interrupts (Depending on IPEN)
INTCONbits.INT0IF = 0; //Clears interrupt 0 flag bit (Must occur before enabling interrupt)
INTCONbits.INT0IE = 1; //Enables the INT0 external interrupt

INTCON2bits.INTEDG0 = 1; //Sets external interrupt 0 to interrupt on rising edge

RCONbits.IPEN = 0; //Disables priority levels on interrupts

TRISBbits.TRISB0 = INPUT; //Sets INT0 as input
TRISBbits.TRISB1 = INPUT; //Sets INT1 as input

}

void main()
{
configure();

while(1)

{
//Program Loop
}
}

//Main interrupt service routine (ISR)
void interrupt ISR()
{
//Check to see if it is interrupt 0
if (INTCONbits.INT0IF == 1)
{
distance++;
INTCONbits.INT0IF = 0; //Clears interrupt flag
}
else
error = 1;
}

Naver

[아두이노 proteus]

가끔 이곳으로 유입되는 사람들중

Proteus와 Arduino의 키워드를 사용해서 들어오는 사람들이 있다.

짐작에는 How to Add Arduino Libraries on Proteus라고 검색했다가

내용이 와닿지 않아서 여기로 오지않았나 싶다.

그래서 정리하고자 한다.

#Arduino Library#아두이노 라이브러리#라이브러리 추가하기

우선 아래 파일을 다운받는다.

Library FIles.zip

안에 꼭 *.IDX 와 *.LIB 확장자인 파일이 있는지 확인한다.

그 다음은 간단하다.

11111

11111

이 두파일을 

C:\Program Files\Labcenter Electronics\Proteus 7 Professional\LIBRARY

여기에 붙여넣기 한다.

따로 폴더를 만들 필요는 없다.

이제 Proteus ISIS를 실행후

마우스우클릭>>Place>>Component>>From Libraries

Keywords: 란에 Arduino라고 타이핑하면

방금 추가한 라이브러리 안의 Arduino를 찾을 수 있다.

PCB추가하기.zip

PCB로 파일이 없을경우 별도로 추가할 필요학 있다.

압축파일안에 순서를 정리했다.

혹시 도움이 필요하신분은 (링크)를 눌러주세요