My board is Arduino Mega 1280 and used memory is FRAM FM25V05.
I used code from http://arduino.cc/en/Tutorial/SPIEEPROM, but I did some modifications.
When I upload the code everything goes fine, but I dont understand that what I get to the serial port or are that ok? First serial prints hi and then only 0, 0, 0, 0 etc.
Code:
#define DATAOUT 51//MOSI
#define DATAIN 50//MISO
#define SPICLOCK 52//sck
#define SLAVESELECT 53//ss chip select
//FM25V05 Op-code Commands
#define WREN 6
#define WRDI 4
#define RDSR 5
#define WRSR 1
#define READ 3
#define WRITE 2
byte eeprom_output_data;
byte eeprom_input_data=0;
byte clr;
int address=0;
//data buffer
char buffer [128];
void fill_buffer()
{
for (int I=0;I<128;I++)
{
buffer[I]=I;
}
}
char spi_transfer(volatile char data)
{
SPDR = data; // Start the transmission
while (!(SPSR & (1<<SPIF))) // Wait the end of the transmission
{
};
return SPDR; // return the received byte
}
void setup()
{
Serial.begin(9600);
pinMode(DATAOUT, OUTPUT);
pinMode(DATAIN, INPUT);
pinMode(SPICLOCK,OUTPUT);
pinMode(SLAVESELECT,OUTPUT);
digitalWrite(SLAVESELECT,HIGH); //disable device
// SPCR = 01010000
//interrupt disabled,spi enabled,msb 1st,master,clk low when idle,
//sample on leading edge of clk,system clock/4 rate (fastest)
SPCR = (1<<SPE)|(1<<MSTR);
clr=SPSR;
clr=SPDR;
delay(100);
//fill buffer with data
fill_buffer();
//fill eeprom w/ buffer
digitalWrite(SLAVESELECT,LOW);
spi_transfer(WREN); //write enable
digitalWrite(SLAVESELECT,HIGH);
delay(10);
digitalWrite(SLAVESELECT,LOW);
spi_transfer(WRITE); //write instruction
address=0;
spi_transfer((char)(address>> 8 )); //send MSByte address first
spi_transfer((char)(address)); //send LSByte address
//write 128 bytes
for (int I=0;I<64;I++)
{
spi_transfer(buffer[I]); //write data byte
}
digitalWrite(SLAVESELECT,HIGH); //release chip
//wait for eeprom to finish writing
delay(3000);
Serial.print('h',BYTE);
Serial.print('i',BYTE);
Serial.print('\n',BYTE);//debug
delay(1000);
}
byte read_eeprom(int EEPROM_address)
{
//READ EEPROM
int data;
digitalWrite(SLAVESELECT,LOW);
spi_transfer(READ); //transmit read opcode
spi_transfer((char)(EEPROM_address>>8 )); //send MSByte address first
spi_transfer((char)(EEPROM_address)); //send LSByte address
data = spi_transfer(0xFF); //get data byte
digitalWrite(SLAVESELECT,HIGH); //release chip, signal end transfer
return data;
}
void loop()
{
eeprom_output_data = read_eeprom(address);
Serial.print(eeprom_output_data,DEC);
Serial.print('\n',BYTE);
//address++;
delay(2000);
if (address == 128)
address = 0;
delay(500); //pause for readability
}
So what's the main problem?
