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/*
* Uuid
*
* UUIDs are unique numbers that are used for identifying individual units,
* functions, programmes, or whatever you want to tag.
*
* In this demo, press the Arduino Reset button to generate a new number.
*
* UUIDs can be assigned sequentially from allocated blocks of numbers, but
* they are most powerful when randomly assigned. UUIDs are such big numbers
* that, for all effective purposes, no two numbers will ever match.
*
* UUIDs are particularly useful in web-aware devices, or radio networks.
*
* For a discussion of the use of UUIDs, see
* http://en.wikipedia.org/wiki/Universally_Unique_Identifier
*
* For implementation details of UUIDs, see
* http://tools.ietf.org/html/rfc4122
*/
#include <TrueRandom.h>
byte uuidNumber[16]; // UUIDs in binary form are 16 bytes long
void printHex(byte number) {
int topDigit = number >> 4;
int bottomDigit = number & 0x0f;
// Print high hex digit
Serial.print( "0123456789ABCDEF"[topDigit] );
// Low hex digit
Serial.print( "0123456789ABCDEF"[bottomDigit] );
}
void printUuid(byte* uuidNumber) {
int i;
for (i=0; i<16; i++) {
if (i==4) Serial.print("-");
if (i==6) Serial.print("-");
if (i==8) Serial.print("-");
if (i==10) Serial.print("-");
printHex(uuidNumber[i]);
}
}
void setup() {
Serial.begin(9600);
// Generate a new UUID
TrueRandom.uuid(uuidNumber);
Serial.print("The UUID number is ");
printUuid(uuidNumber);
Serial.println();
}
void loop() {
}
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