Hi,
I am a beginner with embedded system. Today, I learned some tutorial about SPI of AVR board. However, when I tried to mimic the same thing, I got the problem with the library. Can anyone help me please ? Or a tutorial is extremely good. I tried to search but it seems like there is no.
#ifndef F_CPU
#define F_CPU 16000000UL
#endif
#include <avr32/io.h>
#include <interrupt.h>
#include <util/delay.h>
#include "lcd.h"
#define ACK 0x7E
void spi_init_slave (void)
{
DDRB=(1<<6); //MISO as OUTPUT
SPCR=(1<<SPE); //Enable SPI
}
//Function to send and receive data
unsigned char spi_tranceiver (unsigned char data)
{
SPDR = data; //Load data into buffer
while(!(SPSR & (1<<SPIF) )); //Wait until transmission complete
return(SPDR); //Return received data
}
int main(void)
{
lcd_init(LCD_DISP_ON_CURSOR_BLINK); //Initialize LCD
spi_init_slave(); //Initialize slave SPI
unsigned char data, buffer[10];
DDRA = 0x00; //Initialize PORTA as INPUT
PORTA = 0xFF; //Enable Pull-Up Resistors
while(1)
{
lcd_clrscr(); //LCD Clear screen
lcd_home(); //LCD move cursor to home
lcd_puts("Testing");
lcd_gotoxy(0,1);
data = spi_tranceiver(ACK); //Receive data, send ACK
itoa(data, buffer, 10); //Convert integer into string
lcd_puts(buffer); //Display received data
_delay_ms(20); //Wait
}
}
Error:
