xtest15_1.c

AT91sam7s 256 B/D example

/* ========================================================================== */
/*	 Xtest15_1.c : AT93C56 Read/Write(ORG=0, 256x8 bit, 8-bit SPI)	      */
/* ========================================================================== */
/*			  Designed and programmed by Duck-Yong Yoon in 2007.  */

#include "AT91SAM7S256.h"
#include "lib_AT91SAM7S256.h"
#include "OK7S256ads.h"

void LCD_2hex(unsigned int number)		/* display 2-digit hex number */
{ unsigned char i;

  i = (number >> 4) & 0x0F;			// 16^1
  if(i <= 9) LCD_data(i + '0');
  else       LCD_data(i - 10 + 'A');

  i = number & 0x0F;				// 16^0
  if(i <= 9) LCD_data(i + '0');
  else       LCD_data(i - 10 + 'A');
}

void AT93C56_EWEN(void)		                /* write enable */
{
  AT91F_PIO_SetOutput(AT91C_BASE_PIOA, CS1);	// CS = 1

  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x09, 1);	// 0000 1001
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x80, 1);	// 1000 0000
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?

  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, CS1);	// CS = 0
}

void AT93C56_EWDS(void)		                /* write disable */
{
  AT91F_PIO_SetOutput(AT91C_BASE_PIOA, CS1);	// CS = 1

  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x08, 1);	// 0000 1000
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x00, 1);	// 0000 0000
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?

  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, CS1);	// CS = 0
}

void AT93C56_WRITE(unsigned int address,unsigned int byte) /* write 8 bit */
{
  AT91F_PIO_SetOutput(AT91C_BASE_PIOA, CS1);	// CS = 1

  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x0A, 1);	// 0000 1010
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, address, 1); // A7~A0
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, byte, 1);	// D7~D0
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?

  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, CS1);	// CS = 0
  Delay_ms(10);					// delay 10 ms for twp time
}

unsigned int AT93C56_READ(unsigned int address) /* read a byte */
{
  AT91F_PIO_SetOutput(AT91C_BASE_PIOA, CS1);	// CS = 1

  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x0C, 1);	// 0000 1100
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, address, 1); // A7~A0
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?
  AT91F_SPI_PutChar(AT91C_BASE_SPI, 0x00, 1);	// dummy data
  while(!(*AT91C_SPI_SR & 0x0200));		// transmit complete ?

  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, CS1);	// CS = 0
  return AT91F_SPI_GetChar(AT91C_BASE_SPI);	// read SPI_RDR and return
}

int main(void)
{
  unsigned int address, byte;

  MCU_initialize();				// initialize AT91SAM7S256 & kit
  Delay_ms(50);					// wait for system stabilization
  LCD_initialize();				// initialize text LCD

  LCD_string(0x80," AT93C56 EEPROM ");          // display title
  LCD_string(0xC0,"0x00 = 0x00/0x00");
  Beep();

  AT91F_PIO_CfgOutput(AT91C_BASE_PIOA, CS1);	// PA15 output signal
  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, CS1);	// CS1=0

  AT91F_PIO_CfgOutput(AT91C_BASE_PIOA, PA17);	// PA17=0 for ORG=0
  AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, PA17);

  AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, AT91C_PA12_MISO | AT91C_PA13_MOSI | AT91C_PA14_SPCK, 0);
  						// MISO,MOSI,SPCK output(Peripheral A)

  AT91F_SPI_CfgPMC();				// enable clock of SPI
  *AT91C_SPI_CR = 0x01000001;			// enable SPI
  *AT91C_SPI_MR = 0x00010001;			// master mode
  AT91F_SPI_CfgCs(AT91C_BASE_SPI, 1, 0x3002);	// CS1,1M bps,8 bit,NCPHA=1,CPOL=0

  AT93C56_EWEN();                               // AT93C56 write enable

  for(address = 0x00; address <= 0xFF; address++)
    { LCD_command(0xC2);                        // display address
      LCD_2hex(address);

      LCD_command(0xC9);                        // display write data
      LCD_2hex(0x55);
      AT93C56_WRITE(address,0x55);		// write 0x55
      byte = AT93C56_READ(address);
      LCD_command(0xCE);                        // display read data
      LCD_2hex(byte);
      Delay_ms(500);
      if(byte != 0x55)				// if error, beep
        { Beep();
          Delay_ms(2000);
        }

      LCD_command(0xC9);                        // display write data
      LCD_2hex(0xAA);
      AT93C56_WRITE(address,0xAA);		// write 0xAA
      byte = AT93C56_READ(address);
      LCD_command(0xCE);                        // display read data
      LCD_2hex(byte);
      Delay_ms(500);
      if(byte != 0xAA)				// if error, beep
        { Beep();
          Delay_ms(2000);
        }
    }

  AT93C56_EWDS();                               // AT93C56 write disable

  Beep();
  while(1);					// infinite loop
}