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Import some new EEPROM 2.0 files
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PaulStoffregen committed Apr 2, 2015
1 parent 5e599b8 commit 273d9f9
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50 changes: 50 additions & 0 deletions examples/eeprom_crc/eeprom_crc.ino
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/***
Written by Christopher Andrews.
CRC algorithm generated by pycrc, MIT licence ( https://github.com/tpircher/pycrc ).
A CRC is a simple way of checking whether data has changed or become corrupted.
This example calculates a CRC value directly on the EEPROM values.
The purpose of this example is to highlight how the EEPROM object can be used just like an array.
***/

#include <Arduino.h>
#include <EEPROM.h>

void setup(){

//Start serial
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}

//Print length of data to run CRC on.
Serial.print( "EEPROM length: " );
Serial.println( EEPROM.length() );

//Print the result of calling eeprom_crc()
Serial.print( "CRC32 of EEPROM data: 0x" );
Serial.println( eeprom_crc(), HEX );
Serial.print( "\n\nDone!" );
}

void loop(){ /* Empty loop */ }

unsigned long eeprom_crc( void ){

const unsigned long crc_table[16] = {
0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
};

unsigned long crc = ~0L;

for( int index = 0 ; index < EEPROM.length() ; ++index ){
crc = crc_table[( crc ^ EEPROM[index] ) & 0x0f] ^ (crc >> 4);
crc = crc_table[( crc ^ ( EEPROM[index] >> 4 )) & 0x0f] ^ (crc >> 4);
crc = ~crc;
}
return crc;
}
66 changes: 66 additions & 0 deletions examples/eeprom_get/eeprom_get.ino
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/***
eeprom_get example.
This shows how to use the EEPROM.get() method.
To pre-set the EEPROM data, run the example sketch eeprom_put.
This sketch will run without it, however, the values shown
will be shown from what ever is already on the EEPROM.
This may cause the serial object to print out a large string
of garbage if there is no null character inside one of the strings
loaded.
Written by Christopher Andrews 2015
Released under MIT licence.
***/

#include <EEPROM.h>

void setup(){

float f = 0.00f; //Variable to store data read from EEPROM.
int eeAddress = 0; //EEPROM address to start reading from

Serial.begin( 9600 );
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
Serial.print( "Read float from EEPROM: " );

//Get the float data from the EEPROM at position 'eeAddress'
EEPROM.get( eeAddress, f );
Serial.println( f, 3 ); //This may print 'ovf, nan' if the data inside the EEPROM is not a valid float.

/***
As get also returns a reference to 'f', you can use it inline.
E.g: Serial.print( EEPROM.get( eeAddress, f ) );
***/

/***
Get can be used with custom structures too.
I have separated this into an extra function.
***/

secondTest(); //Run the next test.
}

struct MyObject{
float field1;
byte field2;
char name[10];
};

void secondTest(){
int eeAddress = sizeof(float); //Move address to the next byte after float 'f'.

MyObject customVar; //Variable to store custom object read from EEPROM.
EEPROM.get( eeAddress, customVar );

Serial.println( "Read custom object from EEPROM: " );
Serial.println( customVar.field1 );
Serial.println( customVar.field2 );
Serial.println( customVar.name );
}

void loop(){ /* Empty loop */ }
57 changes: 57 additions & 0 deletions examples/eeprom_iteration/eeprom_iteration.ino
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/***
eeprom_iteration example.
A set of example snippets highlighting the
simplest methods for traversing the EEPROM.
Running this sketch is not necessary, this is
simply highlighting certain programming methods.
Written by Christopher Andrews 2015
Released under MIT licence.
***/

#include <EEPROM.h>

void setup() {

/***
Iterate the EEPROM using a for loop.
***/

for( int index = 0 ; index < EEPROM.length() ; index++ ){

//Add one to each cell in the EEPROM
EEPROM[ index ] += 1;
}

/***
Iterate the EEPROM using a while loop.
***/

int index = 0;

while( index < EEPROM.length() ){

//Add one to each cell in the EEPROM
EEPROM[ index ] += 1;
index++;
}

/***
Iterate the EEPROM using a do-while loop.
***/

int idx = 0; //Used 'idx' to avoid name conflict with 'index' above.

do{

//Add one to each cell in the EEPROM
EEPROM[ idx ] += 1;
idx++;
}while( idx < EEPROM.length() );


} //End of setup function.

void loop(){}
56 changes: 56 additions & 0 deletions examples/eeprom_put/eeprom_put.ino
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/***
eeprom_put example.
This shows how to use the EEPROM.put() method.
Also, this sketch will pre-set the EEPROM data for the
example sketch eeprom_get.
Note, unlike the single byte version EEPROM.write(),
the put method will use update semantics. As in a byte
will only be written to the EEPROM if the data is actually
different.
Written by Christopher Andrews 2015
Released under MIT licence.
***/

#include <EEPROM.h>

struct MyObject{
float field1;
byte field2;
char name[10];
};

void setup(){

Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}

float f = 123.456f; //Variable to store in EEPROM.
int eeAddress = 0; //Location we want the data to be put.


//One simple call, with the address first and the object second.
EEPROM.put( eeAddress, f );

Serial.println("Written float data type!");

/** Put is designed for use with custom structures also. **/

//Data to store.
MyObject customVar = {
3.14f,
65,
"Working!"
};

eeAddress += sizeof(float); //Move address to the next byte after float 'f'.

EEPROM.put( eeAddress, customVar );
Serial.print( "Written custom data type! \n\nView the example sketch eeprom_get to see how you can retrieve the values!" );
}

void loop(){ /* Empty loop */ }
69 changes: 69 additions & 0 deletions examples/eeprom_update/eeprom_update.ino
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/***
EEPROM Update method
Stores values read from analog input 0 into the EEPROM.
These values will stay in the EEPROM when the board is
turned off and may be retrieved later by another sketch.
If a value has not changed in the EEPROM, it is not overwritten
which would reduce the life span of the EEPROM unnecessarily.
Released using MIT licence.
***/

#include <EEPROM.h>

/** the current address in the EEPROM (i.e. which byte we're going to write to next) **/
int address = 0;

void setup(){ /** EMpty setup **/ }

void loop()
{
/***
need to divide by 4 because analog inputs range from
0 to 1023 and each byte of the EEPROM can only hold a
value from 0 to 255.
***/
int val = analogRead(0) / 4;

/***
Update the particular EEPROM cell.
these values will remain there when the board is
turned off.
***/
EEPROM.update(address, val);

/***
The function EEPROM.update(address, val) is equivalent to the following:
if( EEPROM.read(address) != val ){
EEPROM.write(address, val);
}
***/


/***
Advance to the next address, when at the end restart at the beginning.
Larger AVR processors have larger EEPROM sizes, E.g:
- Arduno Duemilanove: 512b EEPROM storage.
- Arduino Uno: 1kb EEPROM storage.
- Arduino Mega: 4kb EEPROM storage.
Rather than hard-coding the length, you should use the pre-provided length function.
This will make your code portable to all AVR processors.
***/
address = address + 1;
if(address == EEPROM.length())
address = 0;

/***
As the EEPROM sizes are powers of two, wrapping (preventing overflow) of an
EEPROM address is also doable by a bitwise and of the length - 1.
++address &= EEPROM.length() - 1;
***/

delay(100);
}
6 changes: 5 additions & 1 deletion keywords.txt
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#######################################
# Syntax Coloring Map For Ultrasound
# Syntax Coloring Map For EEPROM
#######################################

#######################################
# Datatypes (KEYWORD1)
#######################################

EEPROM KEYWORD1
EERef KEYWORD1
EEPtr KEYWORD2

#######################################
# Methods and Functions (KEYWORD2)
#######################################

update KEYWORD2

#######################################
# Constants (LITERAL1)
#######################################
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10 changes: 10 additions & 0 deletions library.properties
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name=EEPROM
version=2.0
author=Arduino, Christopher Andrews
maintainer=Arduino <info@arduino.cc>
sentence=Enables reading and writing to the permanent board storage. For all Arduino boards BUT Arduino DUE.
paragraph=
url=http://arduino.cc/en/Reference/EEPROM
architectures=avr
types=Arduino

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