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@pklaus pklaus/gist:9099457

Created Feb 19, 2014
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/************************************************************************
* Arduino Due: Reading & Writing to I2C EEPROM Version: 1.00 *
* Function : Reads and Writes to Atmel 24C64 Serial EEPROM *
* Exp. Level : Beginner/Elementary *
************************************************************************
* Arduino IDE v1.5.2 from http://arduino.cc/en/Main/Software *
* Configuration: Arduino Due (Programming Port) on /dev/ttyACM0 *
* Operating System: Xubuntu Linux 13.10 Saucy Salamander (32-bit) *
* Created: June 13, 2013 Latest Revision: June 13, 2013 *
************************************************************************
* The Main Ingredients *
* Arduino Due (element14 Order #: 2250861) *
* Atmel 24C64 Serial EEPROM 64K (element14 Order #: 1362657) *
************************************************************************
* Reference Pages *
* Arduino DUE : http://goo.gl/4YRP8 *
* Wire Library: http://goo.gl/6wKis *
* I2C EEPROM : http://goo.gl/vlOR3 *
************************************************************************
*-----------------------Wiring Configuration---------------------------*
* Arduino DUE pin 20 (SDL) to EEPROM pin 5 *
* Arduino DUE pin 21 (SCL) to EEPROM pin 6 *
* Arduino DUE 3.3VDC (VCC) to EEPROM pin 8 <<< ADVISORY!!! *
* Arduino DUE Ground (GND) to EEPROM pins 1, 2, 3, and 4 *
************************************************************************
* MirandaSoft! - Pasig City, Metro Manila, Philippines *
* http://www.element14.com/community/blogs/mirandasoft *
************************************************************************/
#include <Wire.h> // I2C library
void i2c_eeprom_write_byte( int deviceaddress, unsigned int eeaddress, byte data ) {
int rdata = data;
Wire.beginTransmission(deviceaddress);
Wire.write((int)(eeaddress >> 8)); // MSB
Wire.write((int)(eeaddress & 0xFF)); // LSB
Wire.write(rdata);
Wire.endTransmission();
}
// WARNING: address is a page address, 6-bit end will wrap around
// also, data can be maximum of about 30 bytes, because the Wire library has a buffer of 32 bytes
void i2c_eeprom_write_page( int deviceaddress, unsigned int eeaddresspage, byte* data, byte length ) {
Wire.beginTransmission(deviceaddress);
Wire.write((int)(eeaddresspage >> 8)); // MSB
Wire.write((int)(eeaddresspage & 0xFF)); // LSB
byte c;
for ( c = 0; c < length; c++)
Wire.write(data[c]);
Wire.endTransmission();
}
byte i2c_eeprom_read_byte( int deviceaddress, unsigned int eeaddress ) {
byte rdata = 0xFF;
Wire.beginTransmission(deviceaddress);
Wire.write((int)(eeaddress >> 8)); // MSB
Wire.write((int)(eeaddress & 0xFF)); // LSB
Wire.endTransmission();
Wire.requestFrom(deviceaddress,1);
if (Wire.available()) rdata = Wire.read();
return rdata;
}
// maybe let's not read more than 30 or 32 bytes at a time!
void i2c_eeprom_read_buffer( int deviceaddress, unsigned int eeaddress, byte *buffer, int length ) {
Wire.beginTransmission(deviceaddress);
Wire.write((int)(eeaddress >> 8)); // MSB
Wire.write((int)(eeaddress & 0xFF)); // LSB
Wire.endTransmission();
Wire.requestFrom(deviceaddress,length);
int c = 0;
for ( c = 0; c < length; c++ )
if (Wire.available()) buffer[c] = Wire.read();
}
void setup() {
pinMode(13, OUTPUT); // DUE's Pin 13 LED is stuck HIGH
digitalWrite(13, LOW); // Turn off Pin 13 LED
char message[] = "Kuya Marc's Arduino DUE Life"; // data to write
Wire.begin(); // initialise the connection
Serial.begin(9600);
i2c_eeprom_write_page(0x50, 0, (byte *)message, sizeof(message)); // write to EEPROM
delay(10); // add a small delay
Serial.println("Memory written");
}
void loop() {
int addr=0; // first address
byte b = i2c_eeprom_read_byte(0x50, 0); // access the first address from the memory
while (b!=0) {
Serial.print((char)b); // print content to serial port
addr++; // increase address
b = i2c_eeprom_read_byte(0x50, addr); // access an address from the memory
}
Serial.println(" ");
delay(2000);
}
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