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/*
* EEPROM Write
*
* 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.
*/
#include <EEPROM.h>
/** the current address in the EEPROM (i.e. which byte we're going to write to next) **/
int addr = 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;
/***
Write the value to the appropriate byte of the EEPROM.
these values will remain there when the board is
turned off.
***/
EEPROM.write(addr, 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.
***/
addr = addr + 1;
if(addr == EEPROM.length())
addr = 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.
++addr &= EEPROM.length() - 1;
***/
delay(100);
}
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