SyncHome/trunk/Arduino/libraries/spieeprom/spieeprom.cpp

/*
 * spieeprom.cpp - library for SPI EEPROM IC's
 * https://bitbucket.org/trunet/spieeprom/
 * 
 * This library is based on code by Heather Dewey-Hagborg
 * available on http://www.arduino.cc/en/Tutorial/SPIEEPROM
 * 
 * by Wagner Sartori Junior <wsartori@gmail.com>
 */

//#include <WProgram.h>
#include "spieeprom.h"
#include <SPI.h>


SPIEEPROM::SPIEEPROM() {
	eeprom_type = 0;
	address = 0;
}

SPIEEPROM::SPIEEPROM(byte type) {
	if (type>1) {
		eeprom_type = 0;
	} else {
		eeprom_type = type;
	}
	address = 0;
}

void SPIEEPROM::setup() {
	pinMode(SLAVESELECT, OUTPUT);
	SPI.begin();
}

void SPIEEPROM::send_address(long addr) {
	if (eeprom_type == 1) {
		SPI.transfer((byte)(addr>>16));
	}
	SPI.transfer((byte)(addr>>8));
	SPI.transfer((byte)(addr));
}

void SPIEEPROM::start_write() {
	digitalWrite(SLAVESELECT,LOW);
	SPI.transfer(WREN); //send WREN command
	digitalWrite(SLAVESELECT,HIGH);
	digitalWrite(SLAVESELECT,LOW);
	SPI.transfer(WRITE); //send WRITE command
}

bool SPIEEPROM::isWIP() {
	byte data;
	
	digitalWrite(SLAVESELECT,LOW);
	SPI.transfer(RDSR); // send RDSR command
	
	data = SPI.transfer(0xFF); //get data byte
	
	digitalWrite(SLAVESELECT,HIGH);
	
	return (data & (1 << 0));
}

void SPIEEPROM::write(long addr, byte data) {
	start_write();
	
	send_address(addr); // send address
	SPI.transfer(data); // transfer data
	
	digitalWrite(SLAVESELECT,HIGH);
	
	while (isWIP()) {
		delay(1);
	}
}

void SPIEEPROM::write(long addr, byte data[], int arrLength) {
	start_write();
	
	send_address(addr); // send address

	for (int i=0;i<arrLength;i++) {
		SPI.transfer(data[i]); // transfer data
	}
	
	digitalWrite(SLAVESELECT,HIGH);
	while (isWIP()) {
		delay(1);
	}
}

void SPIEEPROM::write(long addr, char data[], int arrLength) {
	start_write();
	
	send_address(addr); // send address
	
	for (int i=0;i<arrLength;i++) {
		SPI.transfer(data[i]); // transfer data
	}
	
	digitalWrite(SLAVESELECT,HIGH);
	while (isWIP()) {
		delay(1);
	}
}

byte SPIEEPROM::read_byte(long addr) {
	byte data;
	
	digitalWrite(SLAVESELECT,LOW);
	SPI.transfer(READ); // send READ command
	
	send_address(addr); // send address
	data = SPI.transfer(0xFF); //get data byte
	
	digitalWrite(SLAVESELECT,HIGH); //release chip, signal end transfer
	
	return data;
}

char SPIEEPROM::read_char(long addr) {
	char data;
	
	digitalWrite(SLAVESELECT,LOW);
	SPI.transfer(READ); // send READ command
	
	send_address(addr); // send address
	data = SPI.transfer(0xFF); //get data byte
	
	digitalWrite(SLAVESELECT,HIGH); //release chip, signal end transfer
	return data;
}