2015年7月24日 星期五

Arduino Weigand 26bit Decoder ---2

Arduino Weigand 26bit Decoder ---2

In Wiegand 26 / Wiegand 34 / Wiegand 36 and all other Wiegand protocols used 2 wires (D0 and D1) to connect reader to MCU.
In standby D0 and D1 connected to VCC(+5V). All data from reader goes in binary format - If reader transmitting 0, it connecting D0 wire to ground for 20-50mks then connecting back to VCC and waits for 2ms before sending next bit. If goes '1' - D1 will be connected to ground fo 20-50mks and so on.
If no change in lines for more than 2ms - transfer complete.
Picture: 



Wiegand protocol — logic level
In logic level wiegand26 have 26 bit of data, 8 for — facility code, 16 for card number, and 2 for parity control.
Facility code – number of building or company where card is used.
Card number – card number 



/*
 * https://github.com/monkeyboard/Wiegand-Protocol-Library-for-Arduino
 */

#include <Wiegand.h>
//I2C + I2C LCD Library 
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);  // set the LCD address to 0x27 for a 16 chars and 2 line display
/*==========================================
SDA – 接 Arduino 的 Analog Pin 4 (Arduino Mega 為 Pin 20)
SCL – 接 Arduino 的 Analog Pin 5 (Arduino Mega 為 Pin 21)
GND – 接 GND
VCC – 接 +5V
==========================================*/

WIEGAND wg;

void setup() {
    Serial.begin(9600);  
    
    wg.begin();
    lcd.init();                      // initialize the lcd
    // Print a message to the LCD.
     lcd.backlight();
    // 輸出初始化文字
    lcd.setCursor(0, 0); // 設定游標位置在第一行行首
    lcd.clear();
    lcd.setCursor(0, 0);                   // 設定游標位置在第1行行首
    lcd.print("Reading RFID....");
    lcd.setCursor(0, 1);                   // 設定游標位置在第2行行首
    lcd.print("Wiegand 26 bit..");
 }

void loop() {
    if(wg.available())
    {   
        lcd.clear();
        lcd.setCursor(0, 0);                   // 設定游標位置在第1行行首
        lcd.print("DEC Code=");
        lcd.print(wg.getCode()); 
        lcd.setCursor(0, 1);                   // 設定游標位置在第2行行首
        lcd.print("HEX Code=");
        lcd.print(wg.getCode(),HEX); 
         
        Serial.print("Wiegand HEX = ");
        Serial.print(wg.getCode(),HEX);
        Serial.print(", DECIMAL = ");
        Serial.print(wg.getCode());
        Serial.print(", Type W");
        Serial.println(wg.getWiegandType());    
    }
}










參考文件: 


4) 程式庫 

   Wiegand 24 and Wiegand 36 Protocol Library for Arduino


char dat[26]; // 26 bit for data
unsigned char fcode; // for facility code (0..255)
unsigned int code; // for card number (0..65535)

while(){

if(PIND.3==0){ // D1 on ground?
 dat[i]=1; //    bit = 1
 i++;
 while(PIND.3==0){};//waiting for release
}

if(PIND.4==0){// D0 on ground?
 dat[i]=0; //  bit = 0
 i++;
    while(PIND.4==0){}; //waiting for release
}

if(i==27) { // i=27, 26 bits collected
 //now parsing
 b=0;
 for(a=9;a>1;a--){ //first 8bit in revers order
  if(dat[a]==1) fcode=fcode+stepen(b); //if bit =1,
             //adding position^2
         //(2^0 , 2^1 , 2^2 and etc)
  b++; // inc position
 }

 b=0; // reset bit counter

 for(a=25;a>9;a--){//same for next 16 bit (card number)
  if(dat[a]==1) code=code+stepen(b);
  b++;
 }
}


//If all OK, we have
//facility code — in var fcode
//card number – in var code

//Now searching...
//all numbers in 2 arrays in eeprom
//unsigned char fcode[MAX];  - facility code
//unsigned int code[MAX];  - card number
//MAX – number of "lines" in memory
// for attiny2313 - 40 code numbers


for(i=0;i<MAX;i++){//going thru array
 // cheching only  facility code in this step
 if(fcode == fcodedb[i]){ //if code found
  //checking number in same position
  if(code==codedb[i]){ //number found...
              //...we have exact numbers
   card_found=1; // flag = card found
   break;  //breaking - no need to check next lines
  }
    }
}

//card found?
if(card_found){//yes!
 PORTD.5=1;//opening lock
 PORTD.6=0;//GREEN LED
 delay_ms(5000); //5 second to enter
 PORTD.5=0;//locking back
 PORTD.6=1;//turning off LED
} else{ //NO! card not found
 PORTB,0=0;//RED led
 delay_ms(3000); //delay for 3 seconds
 PORTB.0=1;//turn of red led
}

//now clear all data
fcode=0; // facility code
code=0; // card number
i=0; // bit counter
card_found=0; // flag

}
//go to first line... and wait for signal on D0 or D1
}



沒有留言:

張貼留言

2024_09 作業3 以Node-Red 為主

 2024_09 作業3  (以Node-Red 為主  Arduino 可能需要配合修改 ) Arduino 可能需要修改的部分 1)mqtt broker  2) 主題Topic (發行 接收) 3) WIFI ssid , password const char br...