/*
RFID Door Lock
10/13/2009
Brett Martin
www.pcmofo.com

Modified by Usama on 21st July 2010 for extra features.....

System for controlling access by reading 125khz RFID cards and compairing the ID tags to stored EEPROM values
Master RFID card used to program new cards into the system. 

ID-12/ID-12 RFID reader

Using sparkfun breakout board
[1] GND (Ground)
[2] /RST (Reset Reader) Connect to +5vDC 
[3] ANT (NC) 
[4] ANT (NC) 
[5] CP (NC) (Card Present) 
[6] NC
[7] FS (Format select) (ground this for ASCII)
[8] D1 (NC)
[9] D0 (TTL Serial) to arduino RX 
[10] Buzzer/LED (Card read indicator) (Connect to transistor + buzzer/led to indicate card was read)
[11] 5v+ ( +5vDC power) 

On Arduino....
[10] (Digital OUT) to Blue LED+
[11] (Digital OUT) to Red LED+
[12] (Digital OUT) to Green LED+
[13] (Digital OUT) to Alarm+
[9] (Digital OUT) to lock relay+ 
[RX0] (Serial IN) to [9] D0 TTL serial out on ID-20


// Based on code by BARRAGAN 
// and code from HC Gilje - http://hcgilje.wordpress.com/resources/rfid_id12_tagreader/
// Modified for Arudino by djmatic
// Modified for ID-12 and checksum by Martijn The - http://www.martijnthe.nl/
// Modified for Deleting cards and wiping memory and alarm by Usama.....
//
// Use the drawings from HC Gilje to wire up the ID-12.
// Remark: disconnect the rx serial wire to the ID-12 when uploading the sketch
*/

#include // Needed to write to EEPROM storage

#define powerPin 10 // Blue LED
#define failPin 11 // Red LED
#define passPin 12 // Grenn LED
#define doorPin 9 // Relay 
#define alarmPin 13 // Alarm

boolean programMode = false; // Initialize program mode to false
boolean deleteMode = false; // Initialize delete mode to false
boolean wipeMode = false; // Initialize wipe mode to false
boolean match = false; // initialize card match to false

byte storedCard[6]; // Stores an ID read from EEPROM
byte readCard[6]; // Sotres an ID read from the RFID reader
byte checksum = 0; // Stores the checksum to verify the ID 

int alarm = 0; // Extra Security 

void setup() 
{
pinMode(powerPin, OUTPUT); // Connected to Blue on tri-color LED to indicate reader is ready
pinMode(passPin, OUTPUT); // Connected to Green on tri-color LED to indicate user is valid
pinMode(failPin, OUTPUT); // Connected to Red on tri-color LED to indicate user is NOT valid or read failed
pinMode(doorPin, OUTPUT); // Connected to relay to activate the door lock
pinMode(alarmPin, OUTPUT); // Connected to alarm
alarm = 0;
Serial.begin(9600); // Connect to the serial port
}

void loop () 
{
byte val = 0; // Temp variable to hold the current byte
normalModeOn(); // Normal mode, blue Power LED is on, all others are off
if (alarm == 3)
{
digitalWrite(alarmPin, HIGH); // Alarm!
Serial.begin(9600);
if(Serial.available() > 0) // Waits for something to come on the serial line
{
if((val = Serial.read()) == 2) // First Byte should be 2, STX byte 
{ 
getID(); // Get the ID, sets readCard = to the read ID
if ( isMaster(readCard) ) // Check to see if it is the master programing card or delete card
{
digitalWrite(alarmPin, LOW);
alarm = 0;
checksum = 0;

}
else
checksum = 0;

}
}
checksum=0;
}
else
{

if ( programMode) // Program mode to add a new ID card
{
programModeOn(); // Program Mode cycles through RGB waiting to read a new card
if(Serial.available() > 0) // Waits for something to come on the serial line
{
if((val = Serial.read()) == 2) // First Byte should be 2, STX byte 
{ 
getID(); // Get the ID, sets readCard = to the read ID
if ( isMaster(readCard) || isDelete(readCard) || isWipe(readCard)) // Check to see if it is the master programing card or delete card
{
programMode = false;
if (isMaster(readCard))
openDoor(2);
else
failedWrite();
checksum = 0;
}
else
{
writeID(readCard); // If not, write the card to the EEPROM sotrage
programMode = false; // Turn off programing mode
checksum = 0; // Make sure the checksum is empty
}
}
}
}
else if ( deleteMode ) // Delete mode to delete an added ID card
{
deleteModeOn(); // Delete Mode cycles through RB waiting to read a new card
if(Serial.available() > 0) // Waits for something to come on the serial line
{
if((val = Serial.read()) == 2) // First Byte should be 2, STX byte 
{ 
getID(); // Get the ID, sets readCard = to the read ID
if ( isMaster(readCard) || isDelete(readCard) || isWipe(readCard) ) // Check to see if it is the master programing card or the Delete Card
{
deleteMode = false;
checksum = 0;
failedWrite();
}
else //if ( !isMaster(readCard) && !isDelete(readCard) )
{
deleteID(readCard); // If not, delete the card from the EEPROM sotrage
deleteMode = false; // Turn off delete mode
checksum = 0; // Make sure the checksum is empty
}
}
}
}
else if ( wipeMode ) // Wipe mode to wipe out the EEPROM
{
Serial.end();
wipeModeOn();
for (int i = 0; i < 512; i++) // Loop repeats equal to the number of array in EEPROM
{
EEPROM.write(i, 0);
}
wipeMode = false;
wipeModeOn();
Serial.begin(9600);
}
// Normal Operation...
else
{
if(Serial.available() > 0) // If the serial port is available and sending data...
{
if((val = Serial.read()) == 2) // First Byte should be 2, STX byte 
{ 
getID(); // Get the ID, sets readCard = to the read ID
byte bytesread = 0;
for ( int i = 0; i < 5; i++ ) // Loop 5 times
{
if ( readCard[i] < 16 ) // Print out 0 if < 16 to prepend output
Serial.print("0");
Serial.print(readCard[i], HEX); // Print out the hex value read in
Serial.print(" ");
}
Serial.println();
Serial.print("Checksum: ");
Serial.print(readCard[5], HEX); // Checksum read from the card
if ( readCard[5] == checksum ) // See if the 5th BYTE (the checksum) read in from the reader
{ // matches the checksum caculated 
checksum = 0; // If so, we can empty the variable storing the calculated checksum
//Serial.println(" passed"); 
//Serial.println();
if ( isMaster( readCard ) ) // Check to see if the card is the master programing card
{
programMode = true; // If so, enable programing mode
alarm = 0;
}
else if ( isDelete( readCard ) ) // Check to see if the card is the deletion card
{
deleteMode = true; // If so, enable deletion mode
alarm = 0;
}
else if ( isWipe( readCard ) ) // Check to see if the card is the deletion card
{
wipeMode = true; // If so, enable deletion mode
alarm = 0;
}
else 
{
if ( findID(readCard) ) // If not, see if the card is in the EEPROM
{
openDoor(2); // If it is, open the door lock
alarm = 0;
}
else
{
failed(); // If not, show that the ID was not valid
alarm++;
}
}
}
else // If the checksum failed
{ // Print out the checksum
/*
Serial.println(" error");
Serial.println();
Serial.print("[");
Serial.print(readCard[5], HEX);
Serial.print("] != [");
Serial.print(checksum, HEX);
Serial.print("] ");
*/
}
}
}
}
}
}

// If the serial port is ready and we received the STX BYTE (2) then this function is called 
// to get the 4 BYTE ID + 1 BYTE checksum. The ID+checksum is stored in readCard[6]
// Bytes 0-4 are the 5 ID bytes, byte 5 is the checksum
void getID()
{
byte bytesread = 0;
byte i = 0;
byte val = 0;
byte tempbyte = 0;
// 5 HEX Byte code is actually 10 ASCII Bytes. 
while ( bytesread < 12 ) // Read 10 digit code + 2 digit checksum
{ 
if( Serial.available() > 0) // Check to make sure data is coming on the serial line
{ 
val = Serial.read(); // Store the current ASCII byte in val
if((val == 0x0D)||(val == 0x0A)||(val == 0x03)||(val == 0x02)) 
{ // If header or stop bytes before the 10 digit reading
break; // Stop reading 
}
if ( (val >= '0' ) && ( val <= '9' ) ) // Do Ascii/Hex conversion
{
val = val - '0';
} 
else if ( ( val >= 'A' ) && ( val <= 'F' ) ) 
{
val = 10 + val - 'A';
}
if ( bytesread & 1 == 1 ) // Every two ASCII charactors = 1 BYTE in HEX format
{
// Make some space for this hex-digit by
// shifting the previous hex-digit with 4 bits to the left:
readCard[bytesread >> 1] = (val | (tempbyte << 4));
if ( bytesread >> 1 != 5 ) // If we're at the checksum byte,
{
checksum ^= readCard[bytesread >> 1]; // Calculate the checksum using XOR
};
} 
else // If it is the first HEX charactor
{
tempbyte = val; // Store the HEX in a temp variable
};
bytesread++; // Increment the counter to keep track
} 
} 
bytesread = 0;
}

// Read an ID from EEPROM and save it to the storedCard[6] array
void readID( int number ) // Number = position in EEPROM to get the 5 Bytes from 
{
int start = (number * 5 ) - 4; // Figure out starting position
//Serial.print("Start: ");
//Serial.print(start);
//Serial.print("\n\n");
for ( int i = 0; i < 5; i++ ) // Loop 5 times to get the 5 Bytes
{
storedCard[i] = EEPROM.read(start+i); // Assign values read from EEPROM to array
/*
Serial.print("Read [");
Serial.print(start+i);
Serial.print("] [");
Serial.print(storedCard[i], HEX);
Serial.print("] \n");
*/
}
}

// Write an array to the EEPROM in the next available slot
void writeID( byte a[] )
{
if ( !findID( a ) ) // Before we write to the EEPROM, check to see if we have seen this card before!
{
int num = EEPROM.read(0); // Get the numer of used spaces, position 0 stores the number of ID cards
/*
Serial.print("Num: ");
Serial.print(num);
Serial.print(" \n");
*/
int start = ( num * 5 ) + 1; // Figure out where the next slot starts
num++; // Increment the counter by one
EEPROM.write( 0, num ); // Write the new count to the counter
for ( int j = 0; j < 5; j++ ) // Loop 5 times
{
EEPROM.write( start+j, a[j] ); // Write the array values to EEPROM in the right position
/*
Serial.print("W[");
Serial.print(start+j);
Serial.print("] Value [");
Serial.print(a[j], HEX);
Serial.print("] \n");
*/
}
successWrite();
}
else
{
failedWrite();
}
}

// Delete an array stored in EEPROM from the designated slot
void deleteID( byte a[] )
{
if ( !findID( a ) ) // Before we delete from the EEPROM, check to see if we have this card!
{
failedWrite(); // If not
}
else 
{
int num = EEPROM.read(0); // Get the numer of used spaces, position 0 stores the number of ID cards
int slot; // Figure out the slot number of the card
int start;// = ( num * 5 ) + 1; // Figure out where the next slot starts
int looping; // The number of times the loop repeats
int j;

int count = EEPROM.read(0); // Read the first Byte of EEPROM that
// Serial.print("Count: "); // stores the number of ID's in EEPROM
// Serial.print(count);
//Serial.print("\n");
slot = findIDSLOT( a ); //Figure out the slot number of the card to delete
start = (slot * 5) - 4;
looping = ((num - slot) * 5);
num--; // Decrement the counter by one
EEPROM.write( 0, num ); // Write the new count to the counter

for ( j = 0; j < looping; j++ ) // Loop the card shift times
{
EEPROM.write( start+j, EEPROM.read(start+5+j)); // Shift the array values to 5 places earlier in the EEPROM
/*
Serial.print("W[");
Serial.print(start+j);
Serial.print("] Value [");
Serial.print(a[j], HEX);
Serial.print("] \n");
*/
}
for ( int k = 0; k < 5; k++ ) //Shifting loop
{
EEPROM.write( start+j+k, 0);
}
successDelete();


}
}
// Find the slot number of the id to be deleted
int findIDSLOT( byte find[] )
{
int count = EEPROM.read(0); // Read the first Byte of EEPROM that
// Serial.print("Count: "); // stores the number of ID's in EEPROM
// Serial.print(count);
//Serial.print("\n");
for ( int i = 1; i <= count; i++ ) // Loop once for each EEPROM entry
{
readID(i); // Read an ID from EEPROM, it is stored in storedCard[6]
if( checkTwo( find, storedCard ) ) // Check to see if the storedCard read from EEPROM 
{ // is the same as the find[] ID card passed
//Serial.print("We have a matched card!!! \n");
return i; // The slot number of the card
break; // Stop looking we found it
} 
}
}

// Check two arrays of bytes to see if they are exact matches
boolean checkTwo ( byte a[], byte b[] )
{
if ( a[0] != NULL ) // Make sure there is something in the array first
match = true; // Assume they match at first

for ( int k = 0; k < 5; k++ ) // Loop 5 times
{
/*
Serial.print("[");
Serial.print(k);
Serial.print("] ReadCard [");
Serial.print(a[k], HEX);
Serial.print("] StoredCard [");
Serial.print(b[k], HEX);
Serial.print("] \n");
*/
if ( a[k] != b[k] ) // IF a != b then set match = false, one fails, all fail
match = false;
}
if ( match ) // Check to see if if match is still true
{
//Serial.print("Strings Match! \n"); 
return true; // Return true
}
else {
//Serial.print("Strings do not match \n"); 
return false; // Return false
}
}

// Looks in the EEPROM to try to match any of the EEPROM ID's with the passed ID
boolean findID( byte find[] )
{
int count = EEPROM.read(0); // Read the first Byte of EEPROM that
// Serial.print("Count: "); // stores the number of ID's in EEPROM
// Serial.print(count);
//Serial.print("\n");
for ( int i = 1; i <= count; i++ ) // Loop once for each EEPROM entry
{
readID(i); // Read an ID from EEPROM, it is stored in storedCard[6]
if( checkTwo( find, storedCard ) ) // Check to see if the storedCard read from EEPROM 
{ // is the same as the find[] ID card passed
//Serial.print("We have a matched card!!! \n");
return true;
break; // Stop looking we found it
}
else // If not, return false
{
//Serial.print("No Match here.... \n");
}

}
return false;
}

// Opens door and turns on the green LED for setDelay seconds
void openDoor( int setDelay )
{
setDelay *= 1000; // Sets delay in seconds
Serial.end();
digitalWrite(powerPin, LOW); // Turn off blue LED
digitalWrite(failPin, LOW); // Turn off red LED
digitalWrite(passPin, HIGH); // Turn on green LED
digitalWrite(doorPin, HIGH); // Unlock door!

delay(setDelay); // Hold door lock open for 2 seconds

digitalWrite(doorPin, LOW); // Relock door

delay(setDelay); // Hold green LED om for 2 more seconds

digitalWrite(passPin, LOW); // Turn off green LED
Serial.begin(9600);
}

// Flashes Red LED if failed login
void failed()
{
Serial.end();
digitalWrite(passPin, LOW); // Make sure green LED is off
digitalWrite(powerPin, LOW); // Make sure blue LED is off
// Blink red fail LED 3 times to indicate failed key
digitalWrite(failPin, HIGH); // Turn on red LED
delay(1200); 
Serial.begin(9600);
}

// Check to see if the ID passed is the master programing card
boolean isMaster( byte test[] ) 
{
byte bytesread = 0;
byte i = 0; // Example card, replace with one of yours you want to be the master
byte val[10] = {'2','9','0','0','9','4','0','F','F','3' }; 
byte master[6];
byte checksum = 0;
byte tempbyte = 0;
bytesread = 0; 

for ( i = 0; i < 10; i++ ) // First we need to convert the array above into a 5 HEX BYTE array
{
if ( (val[i] >= '0' ) && ( val[i] <= '9' ) ) // Convert one char to HEX
{
val[i] = val[i] - '0';
} 
else if ( (val[i] >= 'A' ) && ( val[i] <= 'F' ) ) 
{
val[i] = 10 + val[i] - 'A';
} 
if (bytesread & 1 == 1) // Every two hex-digits, add byte to code:
{
// make some space for this hex-digit by
// shifting the previous hex-digit with 4 bits to the left:
master[bytesread >> 1] = (val[i] | (tempbyte << 4)); 
if (bytesread >> 1 != 5) // If we're at the checksum byte,
{
checksum ^= master[bytesread >> 1]; // Calculate the checksum... (XOR)
};
} 
else 
{
tempbyte = val[i]; // Store the first hex digit first...
};
bytesread++; 
} 
if ( checkTwo( test, master ) ) // Check to see if the master = the test ID
return true;
else
return false;
}

// Check to see if the ID passed is the wipe memory card
boolean isWipe( byte test[] ) 
{
byte bytesread = 0;
byte i = 0; // Example card, replace with one of yours you want to be the master
byte val[10] = {'2','9','0','0','9','3','D','8','7','F' }; 
byte master[6];
byte checksum = 0;
byte tempbyte = 0;
bytesread = 0; 

for ( i = 0; i < 10; i++ ) // First we need to convert the array above into a 5 HEX BYTE array
{
if ( (val[i] >= '0' ) && ( val[i] <= '9' ) ) // Convert one char to HEX
{
val[i] = val[i] - '0';
} 
else if ( (val[i] >= 'A' ) && ( val[i] <= 'F' ) ) 
{
val[i] = 10 + val[i] - 'A';
} 
if (bytesread & 1 == 1) // Every two hex-digits, add byte to code:
{
// make some space for this hex-digit by
// shifting the previous hex-digit with 4 bits to the left:
master[bytesread >> 1] = (val[i] | (tempbyte << 4)); 
if (bytesread >> 1 != 5) // If we're at the checksum byte,
{
checksum ^= master[bytesread >> 1]; // Calculate the checksum... (XOR)
};
} 
else 
{
tempbyte = val[i]; // Store the first hex digit first...
};
bytesread++; 
} 
if ( checkTwo( test, master ) ) // Check to see if the master = the test ID
return true;
else
return false;
}

// Check to see if the ID passed is the deletion card
boolean isDelete( byte test[] ) 
{
byte bytesread = 0;
byte i = 0; // Example card, replace with one of yours you want to be the deletion
byte val[10] = {'2','9','0','0','9','4','2','0','4','2' }; 
byte master[6];
byte checksum = 0;
byte tempbyte = 0;
bytesread = 0; 
for ( i = 0; i < 10; i++ ) // First we need to convert the array above into a 5 HEX BYTE array
{
if ( (val[i] >= '0' ) && ( val[i] <= '9' ) ) // Convert one char to HEX
{
val[i] = val[i] - '0';
} 
else if ( (val[i] >= 'A' ) && ( val[i] <= 'F' ) ) 
{
val[i] = 10 + val[i] - 'A';
} 
if (bytesread & 1 == 1) // Every two hex-digits, add byte to code:
{
// make some space for this hex-digit by
// shifting the previous hex-digit with 4 bits to the left:
master[bytesread >> 1] = (val[i] | (tempbyte << 4)); 
if (bytesread >> 1 != 5) // If we're at the checksum byte,
{
checksum ^= master[bytesread >> 1]; // Calculate the checksum... (XOR)
};
} 
else 
{
tempbyte = val[i]; // Store the first hex digit first...
};
bytesread++; 
} 
if ( checkTwo( test, master ) ) // Check to see if the delete = the test ID
return true;
else
return false;
}

// Controls LED's for Normal mode, Blue on, all others off
void normalModeOn()
{
digitalWrite(powerPin, HIGH); // Power pin ON and ready to read card
digitalWrite(passPin, LOW); // Make sure Green LED is off
digitalWrite(failPin, LOW); // Make sure Red LED is off
digitalWrite(doorPin, LOW); // Make sure Door is Locked 
}

// Controls LED's for program mode, cycles through RGB
void programModeOn()
{
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, LOW); // Make sure blue LED is off
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, HIGH); // Make sure blue LED is on
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is on
digitalWrite(failPin, LOW); // Make sure blue LED is off
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
}

// Controls LED's for delete mode, cycles through RB
void deleteModeOn()
{
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, HIGH); // Make sure red LED is on
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is on
digitalWrite(failPin, LOW); // Make sure red LED is off
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
}

// Flashes the green LED 3 times to indicate a successful write to EEPROM
void successWrite()
{
Serial.end();
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, LOW); // Make sure red LED is off
digitalWrite(passPin, LOW); // Make sure green LED is on
delay(200);
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
Serial.begin(9600);
}

// Flashes the red LED 3 times to indicate a failed write to EEPROM
void failedWrite()
{
Serial.end();
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, LOW); // Make sure red LED is on
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(failPin, HIGH); // Make sure red LED is on
delay(200);
digitalWrite(failPin, LOW); // Make sure red LED is off
delay(200);
digitalWrite(failPin, HIGH); // Make sure red LED is on
delay(200);
digitalWrite(failPin, LOW); // Make sure red LED is off
delay(200);
digitalWrite(failPin, HIGH); // Make sure red LED is on
delay(200);
Serial.begin(9600); 
}

// Flashes the blue LED 3 times to indicate a success delete to EEPROM
void successDelete()
{
Serial.end();
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, LOW); // Make sure red LED is off
digitalWrite(passPin, LOW); // Make sure green LED is on
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is off
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is off
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is off
delay(200);
Serial.begin(9600);
}

// Controls LED's for wipe mode, cycles through BG
void wipeModeOn()
{
digitalWrite(powerPin, LOW); // Make sure blue LED is off
digitalWrite(failPin, LOW); // Make sure red LED is off
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(50);
digitalWrite(powerPin, HIGH); // Make sure blue LED is on 
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off 
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
digitalWrite(powerPin, HIGH); // Make sure blue LED is on 
digitalWrite(passPin, LOW); // Make sure green LED is off
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off 
digitalWrite(passPin, HIGH); // Make sure green LED is on
delay(200);
digitalWrite(powerPin, LOW); // Make sure blue LED is off 
digitalWrite(passPin, LOW); // Make sure green LED is on
delay(200);
digitalWrite(failPin, HIGH); // Make sure green LED is on
}

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http://www.sparkfun.com/commerce/product_info.php?products_id=8310

Door Fail Secure access control Electric Strike v5 NO $17.50 (kawamall, bay)
http://cgi.ebay.com/Door-Fail-Secure-access-control-Electric-Strike-v5-NO_W0QQitemZ350230332833QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518b5ac5a1#ht_3787wt_1167
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