Attendance Record System

void _cmd(byte cmd,int number)
{
 if(number>767)
 {
  msg("INVALID ID");
  return;
 }

 Serial.begin(57600);

 byte packet_content;
 switch(cmd)
 {
  case SEARCH_FINGERPRINT:packet_content=5;break;
  case EMPTY_DATABASE:packet_content = 1;break;
  default: packet_content = 3;break;
 }

 byte Hbyte = number/256;
 byte Lbyte = number%256;
 byte checksum = 0;

 byte send_cmd[packet_content+5];
 for(byte i=0;i<sizeof(send_cmd);i++) 
 send_cmd[i]=0;

 send_cmd[0] = 0x4D;
 send_cmd[1] = 0x58;
 send_cmd[2] = 0x10;
 send_cmd[3] = packet_content;
 send_cmd[4] = cmd;

 for(byte i=0;i<sizeof(send_cmd);i++)
 checksum+=send_cmd[i];

 if(packet_content>=3)
 {
  send_cmd[5] = Hbyte;send_cmd[6] = Lbyte;
  checksum+=send_cmd[5];
  checksum+=send_cmd[6];

  if(cmd==SEARCH_FINGERPRINT)
  {
   for(byte i=7;i>4;i--)
   send_cmd[i+2]=send_cmd[i];

   send_cmd[5] = 0;send_cmd[6] = 0;
   checksum+=send_cmd[5];
   checksum+=send_cmd[6];
  }
 }

 send_cmd[packet_content+5-1]=checksum;

 Serial.write(send_cmd,sizeof(send_cmd));
 delay(1);
}

• byte cmd refers to which command the user wants to execute.For example: if user wants to add fingerprint, cmd should be 0x40. int number refers to fingerprint id(position) in the module. If the command doesn’t require id number, just put any number.

• The command should not be sent if id/position is more than 767 (the module can only store up to  the 768 fingerprints only), or else you will receive parameter error from device.

• Initialize the serial communication at baud rate 57600 as stated in user manual.

• packet_content will be determined by the cmd value you just inserted. Most of the command has packet content length of 3 bytes. Search fingerprint and empty database are the exceptions.

• Determine high byte and low byte of the id number.

• Declare an array of bytes with variable size to be sent to module and initialize it.

• Start putting appropriate values to the array. 0x4D as first byte, 0x58 as second byte and so forth. Please refer to fingerprint module user manual to verify the correctness of packet data.

• Calculate the checksum for first time.

• If the packet content length equal or more than 3 bytes, add high byte of number as 5th byte and low byte as 6th byte. Calculate the checksum. Take note that commands with packet content length less than 3 bytes will not go through this part.

• If the command is search fingerprint command, shift value from 5th byte to 7th byte and 6th byte to 8th byte. Now 5th byte and 6th byte should be replaced with high byte and low byte of a number respectively where this number is the number that module will start searching from. Here we put 0 in both bytes, thus searching will start from 0. Recalculate the checksum.

• Put the value of final checksum as last byte.

• Send this string of bytes to the module. Give some delays.

boolean _respond(byte cmd)
{
  boolean end_flag = false;
  boolean success = false;
  byte addfp_count = 0;
  while(!end_flag)
  {
    int packet_length = 9;
    byte resp_temp[packet_length];
    for(byte j=0;j<packet_length;j++)
    { 
      while(Serial.available()==0)
      {
        //you can add something here
      }
     resp_temp[j]=Serial.read();
     if(j==3) packet_length = resp_temp[3]+5;
    }

   switch(resp_temp[5])
   {
    case OP_SUCCESS:
    if(cmd==SEARCH_FINGERPRINT) 
     //add something here
    else if(cmd==ADD_FINGERPRINT) 
    { 
     //add something here
     addfp_count++;
    }
    else if(cmd==DELETE_FINGERPRINT)
    {
     //add something here
     end_flag = true;
     success = true;
    }
    else if(cmd==EMPTY_DATABASE)
    {
     //add something here
     end_flag = true;
     success = true;
    }
    break;

    case TIME_OUT:
    //add something here
    end_flag=true;
    break;

    case PROCESS_FAILED:
    //add something here
    end_flag=true;
    break;

    case PARAMETER_ERR:
    //add something here
    end_flag=true;
    break;

    case MATCH:
    //add something here
    success = true;
    end_flag=true;
    break;

    case NO_MATCH:
    // add something here
    end_flag=true;
    break;
    
    case FP_FOUND:
    //add something here
    worker_id = response[6]*256+response[7];
    end_flag=true;
    success = true;
    break;

    case FP_UNFOUND:
    //add something here
    end_flag=true;
    break;
   }
  
   if(cmd==byte(ADD_FINGERPRINT)&&addfp_count>1)
   {
    //add something here
    success = true;
    end_flag=true;
   }

  }
 Serial.end();
 return success;
}

• byte cmd refers to the previous command the user sends to module.

• Initialize some variables
• end_flag – determines when this function should terminate
• success – determines whether the operation performs successfully
• addfp_count – this variable is made for adding fingerprint process. Adding fingerprint process requires 2 responses to be successful. addfp_count determines when the function ends.

• Create a temporary array for received packets. Initialise the array with the size of 9.

• Read and store the received bytes. When 4th byte is read, total data packet length is determined.

• Determine high byte and low byte of the id number.

• Declare an array of bytes with variable size to be sent to module and initialize it.

• In attendance system, search fingerprint command is constantly sent to module. If there is no finger on screen within about 10 secs, time out response will be received. Before this response is received, the program will continue in this loop(red highlighted). And also once the command is sent, fingerprint module will not receive any other commands and do anything until the response for the current command is given out. Therefore user can put in some functions like time display.

• Check the 6th byte of received data and carry out functions according to response code

• //add something here is the place where you can put your own functions like light up LED, make beep sound from buzzer or display words on LCD

• this function is boolean/bool type, which returns value of success. User may modify the function to any appropriate types and return something in which user think is useful for next operation. User may change to void type to return nothing.

• If search fingerprint is successful, 6th and 7th bytes will be the id number that module returns for corresponding fingerprint. User may want to define a variable to store the number. In this tutorial, we declare a global variable worker_id to store the number.

void wrFlash(int id,int type,String data2wr)
{
 Serial.begin(57600);
 char data[data2wr.length()+1];
 data2wr.toCharArray(data,data2wr.length()+1);

 if(sizeof(data)>128) {msg("too big");return;}

 byte wr_data[sizeof(data)+9];
 byte checksum = 0;
 byte i;

 wr_data[0] = 0x4D;
 wr_data[1] = 0x58;
 wr_data[2] = 0x10;
 wr_data[3] = 4 + sizeof(data);
 wr_data[4] = 0x64;
 wr_data[5] = ((id-1)*ADDR + type)/256;
 wr_data[6] = ((id-1)*ADDR + type)%256;
 wr_data[7] = sizeof(data);

 for(i = 0;i<sizeof(data);i++) wr_data[i+8] = data[i];

 for(i=0;i<(sizeof(wr_data)-1);i++) checksum+= wr_data[i];

 wr_data[sizeof(wr_data)-1] = checksum;

 Serial.write(wr_data,sizeof(wr_data));
 delay(1);

 char rx[6];
 while(Serial.available()==0){}
 Serial.readBytes(rx,6);

 if(rx[3]==0x01&&rx[4]==0x02) 
 {
  //do something here if receive packet error
  return;
 }

 char ops_[7];
 while(Serial.available()==0){}
 Serial.readBytes(ops_,7);

 if(ops_[5]!=OP_SUCCESS) 
 {
  //do something here if storing data not successful
  return;
 }
 Serial.end();

}

• This function is customized and int id and type are used to determine the address for the data to be stored. User can modify these 2 parameters.

• Initialise the serial communication and convert string to char array.

• According to user manual, only 128 bytes are allowed to be written at one time.

• Initialise an array to store the bytes to be sent to the module and put necessary values to each byte.

• wr_data[5] refers to the high byte of address and wr_data[6] refers to low byte of address. User may modify these 2 lines.

• send the data bytes to module and waiting for response.

• First response is to check whether it is packet error or not.

• Second response is to check whether writing data to memory is successful or not.

• Take note**: 1 address only stores 1 byte of data. Let say you want to store “Cytron” string, 7 consecutive addresses are needed (including null character). In this function you only have to send the starting address to the module. If you want to store multiple data, consider to plan the address properly or else you will find the data overlapped.

char* rdFlash(int id,int type,byte num)
{ 
 Serial.begin(57600);
 if(num>128) {msg("too big");return 0;}

 byte rd_data[9];
 byte checksum = 0;
 byte i;

 rd_data[0] = 0x4D;
 rd_data[1] = 0x58;
 rd_data[2] = 0x10;
 rd_data[3] = 0x04;
 rd_data[4] = 0x62;
 rd_data[5] = ((id-1)*ADDR + type)/256;
 rd_data[6] = ((id-1)*ADDR + type)%256;
 rd_data[7] = num;
 for(i=0;i<8;i++) checksum+= rd_data[i];

 rd_data[8] = checksum;
 Serial.write(rd_data,sizeof(rd_data));
 delay(1);

 char rx[6];
 while(Serial.available()==0){}
 Serial.readBytes(rx,6);

 if(rx[3]==0x01&&rx[4]==0x02) 
 {
  //do something here if receive packet error 
  return 0;
 }

 char ops_[6+num];
 while(Serial.available()==0){}
 Serial.readBytes(ops_,sizeof(ops_));

 char dat[num];
 for(i=0;i<num;i++) dat[i] = ops_[i+5]; 

 Serial.end();
 return dat; 
}

• This function is customized and int id and type are used to determine the starting address for the data to be read. User can modify these 2 parameters. byte num refers to the length of data you want to read.

• Initialise the serial communication. Same as before, only 128 bytes are allowed to be read at one time.

• Initialise an array to store the bytes to be sent to the module and put necessary values to each byte to initiate reading data from module.

• rd_data[5] refers to the high byte of address and rd_data[6] refers to low byte of address. User may modify these 2 lines.

• send the data bytes to module and waiting for response.

• First response is to check whether it is packet error or not.

• Second response from module contains the data bytes the user requests from address. User can create a variable to store these data bytes. Here we declare function as char array type and will return the data if the function ends. User can modify the function type to suit their application.

• Note**: the only thing you have to care about is the num value. Make sure that you know the size of the data you want to read. Let say you want to read “Ahmad” from module you can set num = 8, 6 for the data(including null terminator) and 2 for extra length.

boolean checkSDCard()
{ 
 boolean SDCard_status = card.init(SPI_HALF_SPEED,chipSelect);
 if (!SDCard_status||!vol.init(&card)) 
 { 
  //do something here if card is not detected
 }

 uint32_t volumesize= vol.blocksPerCluster()*vol.clusterCount()*512;
 uint32_t freespace = 512*vol.freeClusterCount()*vol.blocksPerCluster();

 //check free space available
 if(freespace==0) 
 //do something here if memory is full
 else if(freespace<0.1*volumesize) 
 //do something here if memory is nearly full
 
 return true;
}

• This function is to check SD card condition and returns true value if card is detected.

• card.init is to initialise the card and vol.init is to initialise the accessing volume of the card. Both functions returns true if the process is completed. It is advisable to check these 2 functions to see whether the card is detected or not.

• In this function, calculation of total volume size and free space available is included. User can use this to check the availability of the card to store data.

void record(String dataString)
{ 
 // do something here to indicate recording/storing
 char filename[fileName.length()+1];
 fileName.toCharArray(filename,fileName.length()+1);

 //checking card condition
 if (!sd.begin(chipSelect, SPI_HALF_SPEED))
 {
  if(!checkSDCard())
  {
   // do something if card failed
  }
 }

 boolean title=false;
 if(!sd.exists(filename)) title = true;

 // create or open file
 SdFile dataFile;
 if(title==true)
 { 
  SdFile::dateTimeCallback(dateTime);
  dataFile.open(filename,O_WRITE| O_CREAT| O_APPEND);
  dataFile.println("Date,Time,Worker ID,Status,Remark,");
  dataFile.close();
  title = false;
 }

 else dataFile.open(filename, O_WRITE| O_APPEND);

// if the file isn't open, pop up an error:
 if (!dataFile.isOpen()) 
 {
  // do something if file cannot be opened
 } 
 else
 {// if the file is available, write to it:
  dataFile.println(dataString);
  dataFile.close();
 }

• This function is to store strings to a file in microSD. String dataString is the employee’s login and logout string info ready to be stored.

• Highlighted lines are the codes to convert string to const char* type. This string is the target filename.

• If the file doesn’t exist, create a new one. Function dateTimeCallback(dateTime) is to detemine the time when the file is created, so that when user is accessing the file using computer or other devices, he or she can see the proper created time and date for the file. If this function is not called, the date will be incorrect. This function is only working with the installation of RTC_module.

• O_WRITE only in file open will cause the data in existing file to be overwritten. To store data without overwritting the existing data, use O_WRITE|O_APPEND instead.

void rdAdmin()
{
 SdFile dataFile;
 if (!sd.begin(chipSelect, SPI_HALF_SPEED))
 {
 if(!checkSDCard())
 {
  //do something here if card failed
 }
 }
 if (!dataFile.open("admin.csv", O_READ))
 {
  //do something here if file not opened
 }
 char data;
 String worker_data[5];
 int count = 0;
 boolean title_flag = true;
 int line_count = 0;
 
 while ((data = dataFile.read()) >= 0)
 {
 if(data!=','&&int(data)!=13&&int(data)!=10) 
  worker_data[count]+=String(data);
 else if(data==',') count++;
 else if(int(data)==13) //if read data jumps to next line
 {
 dataFile.read();
 if(line_count>0)
 {
  wrFlash((worker_data[0].toInt()),ID,worker_data[0]);
  wrFlash((worker_data[0].toInt()),NAME,worker_data[1]);
  wrFlash((worker_data[0].toInt()),POS,worker_data[2]);
 }
 line_count++;
 count = 0;
 memset(worker_data,0,sizeof(worker_data));
 }
 }

 dataFile.close();
 }

• This function is to read employees’ info from a file named “admin.csv” in microSD.

• dataFile.read() reads character by character. If no data can’t be read(at the end of file), data will be < 0.

• This function also implements wrFlash function. The data read will be stored in fingerprint module flash memory.

• An temporary array with size 5 is declared to store worker’s data, one for one type (although only 3 types to be stored).

• The file read is in CSV format (comma separated), thus this algorithm uses comma to separate read data and store into different array.

• If next line is reached, the arrays are reset so that new data can be stored. next line will be indicated by int data 13(carriage return)and 10(new line feed). User can refer to ASCII code table.

• There is also a SD library function call fgets() which reads line by line. In this project some of the functions implement this. User can have a guide.

void Time_Display()
{
 lcd.setCursor(0,1);

 lcd.print(Wday[weekday()-1]);lcd.print(" ");
 lcd.setCursor(0,0);

 printDigits(day());
 lcd.print("-");
 printDigits(month());
 lcd.print("-");
 printDigits(year()%100);

 lcd.setCursor(11,0);
 printDigits(hourFormat12());
 lcd.print(":");
 printDigits(minute());
 //lcd.print(":");lcd.print(second());

 lcd.setCursor(14,1);

 if(isAM()==1){
 lcd.print("AM");
 }

 else{
 lcd.print("PM");
 }

}

void printDigits(int digits)
{
 if(digits < 10)
 lcd.print('0');
 lcd.print(digits);
}

• This function is to display the current time on LCD display. This function implements LCD display function which is from LiquidCrystal.h library.

• Available function from Time.h library:
  • year() – returns the value of current year
  • month() – returns the value of current month
  • day() – returns the value of current day
  • weekday() – returns the value of current week day
  • e.g. Sunday – 0, Monday – 1, etc.
  • hour() – returns the value of current hour in 24 format
  • hourFormat12() – returns value of current hour in 12 format
  • isAM() – returns true if it is AM
  • isPM() – returns true is it is PM
  • minute() – returns the value of current minute
  • second()- returns the value of current second

• printDigits() function converts number into 2 digits display.

• User can even display the specific details of past time or future time. For example:

time_t tim = now()+3600; //3600 seconds

printDigits(hour(tim));

User will find that the display time will be 1 hour past the            current time.

void setup_Time()
{ 
 byte lcd_hpos[7]={0,3,6,11,14,14};
 byte lcd_vpos[7]={0,0,0,0,0,1};
 int lcd_pos = 0;

 int cur_time=millis();
 int prev_time=millis();
 boolean display_stat;
 boolean time_update = 0;
 int localKey;

 Time_Display();
while(1)
 {
 int sec_update = second();
 int min_update = minute();
 int hour_update = hour();
 int day_update = day();
 int month_update = month();
 int year_update = year();

 localKey = keypad.getKey();

 cur_time = millis();
 if(cur_time-prev_time>400)
 {
 display_stat = !display_stat;
 prev_time = cur_time;
 }

 if(display_stat==true)
 {
 lcd.setCursor(lcd_hpos[lcd_pos],lcd_vpos[lcd_pos]);
 lcd.print(" ");
 }
 else
 {
 Time_Display();
 } 

 if(localKey==Select)
 {
 if(time_update==true) 
  setTime(hour(),minute(),0,day(),month(),year());
 RTC.set(now());
 msg("UPDATING TIME");
 }

 else if(localKey==Left)
 {
 if(--lcd_pos<0) lcd_pos = 5;
 delay(pb_delay);
 }

 else if(localKey==Right)
 {
 if(++lcd_pos>5) lcd_pos = 0;
 delay(pb_delay);
 }

 else if(localKey==Up)
 {
 switch(lcd_pos)
 {
 case 0: day_update++; if(day_update>31) day_update=1;break;
 case 1: month_update++; if(month_update>12) month_update =1;break;
 case 2: year_update++; if(year_update>2100) year_update = 2013;break;
 case 3: hour_update++;
 if(isAM()==1){if(hour_update>11) hour_update =0;}
 else if(isPM()==1){if(hour_update>23) hour_update =12;}
 time_update = 1;break;
 case 4: min_update++;if(min_update>59) min_update =0;
 time_update = 1;break;
 case 5: if(isAM()==1)hour_update+=12;else hour_update-=12;break;
 }
 setTime(hour_update,min_update,sec_update,day_update,
 month_update,year_update);
 Time_Display();
 delay(pb_delay);
 }

 else if(localKey==Down)
 {
 switch(lcd_pos)
 {
 case 0: day_update--;if(day_update<1) day_update = 31;break;
 case 1: month_update--;if(month_update<1) month_update = 12;break;
 case 2: year_update--; if(year_update<2013) year_update = 2013;break;
 case 3: hour_update--; 
 if(isAM()==1){if(hour_update<0) hour_update =11;}
 else if(isPM()==1) {if(hour_update<12) hour_update =23;}
 time_update = 1;break;
 case 4: min_update--;if(min_update<0) min_update =59;time_update = 1;break;
 case 5: if(isAM()==1) hour_update+=12; else hour_update-=12;break;
 }
 setTime(hour_update,min_update,second(),day_update,
 month_update,year_update);
 Time_Display();
 delay(pb_delay);
 }
 }
}

• This function is to change and set the current time and update the time to RTC module. This function implements LCD display function and LCD navigation buttons from LCD_Key.h library.

• In this program, left and right buttons are used to switch to specific type like day, month,year,hour,minute and AM/PM. Up and down buttons are used to change the value. Select button is to update the set time to RTC module.

• Highlighted part is to blink the time type user current choose to change and serves as indicator
• pb_delay is delay time set. Here pb_delay = 200;

//global variables for admin menu and interface
byte choice[2];
byte page_no;

void admin()
{
 int category = 0;
 int page = 0;
 int localKey;

 selection(category,page);// display first page
 while(1)
 {
 if(reset_)
 {
  category-=1;
  page = choice[category];
  selection(category,page);
  reset_=false;
 }
 localKey = keypad.getKey();

 switch(localKey)
 {
 case Left: page--;
 if(page<0) page = 0;
 else if(page>page_no-1) page = page_no-1;
 selection(category,page);
 delay(200);
 break;

 case Right: page++;
 if(page<0) page = 0;
 else if(page>page_no-1) page = page_no-1;
 selection(category,page);
 delay(200);
 break;

 case Select:
 choice[++category] = page;
 choice[category-1] = choice[category];
 lcd.clear();
 selection(category,page);
 delay(200);
 break;
 
 case Up: category--;
 if(category<0)
 {
 lcd.clear();
 return;
 }
 else
 page = choice[category];
 lcd.clear();
 selection(category,page);
 delay(200);
 break;
 }
 }
}
void selection(int category,int page){
switch(category)
 {
 case 0: 
 page_no = 5;//set pages for first category
 menu(page);
 break;

 case 1:
 if(choice[category]==0){delay(pb_delay);//add function here} 
 else if(choice[category]==1){delay(pb_delay);//add function here}
 else if(choice[category]==2){delay(pb_delay);//add function here}
 else if(choice[category]==3){delay(pb_delay);//add function here}
 else if(choice[category]==4){delay(pb_delay);//add function here}
 //user can add more function here
 reset_ = true;
 break; 
 }
}
void menu(int page){
 lcd.clear();
 lcd.setCursor(0,0);
 lcd.print("Menu ");
 lcd.print(page+1);lcd.print(":");
switch(page)
 {
 case 0: //customise first page// break;
 case 1: //customise second page// break;
 case 2: //customise third page// break; 
 case 3: //customise forth page// break;
 case 4: //customise fifth page// break; 
 //user can add more here
 }
}

• To use this interface, user just need to know how many options that needed to be created in the menu. Let say if 4 options are needed, change the value of page_no in void selection() to 4. Page_no determines how many options you want to set in the menu.

• In void menu(), it is for user to design the page for each menu option. The most common way is to display the title of the menu.

• In void selection() under case 1, user can add extra functions that dedicated to choice[category], like “else if(choice[category]==5){delay(pb_delay);//add function here}”. choice[category] is the menu option you selected, if you choose first menu option, choice[category] will be 0, then you can execute whatever function you want in this menu.