spi.c

LPC2148 通过 SPI 口 读写 AT26DF081 EEPROM的源程序

/*****************************************************************************
 *   spi.c:  SPI C file for Philips LPC214x Family Microprocessors
 *
 *   Copyright(C) 2006, Philips Semiconductor
 *   All rights reserved.
 *
 *   History
 *   2005.10.01  ver 1.00    Prelimnary version, first Release
 *
*****************************************************************************/
#include "config.h"

#include "spi.h"

volatile uint32 SPI0Status = 0;
volatile uint32 TxCounter = 0;
extern uint8 SPICmd[BUFSIZE];
extern uint8 SPIWRData[BUFSIZE];
extern uint8 SPIRDData[BUFSIZE];
/*****************************************************************************
** Function name:		SPI0Handler
**
** Descriptions:		SPI0 interrupt handler
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/


/*****************************************************************************
** Function name:		SPIInit
**
** Descriptions:		SPI port initialization routine
**				
** parameters:			None
** Returned value:		true or false, if the interrupt handler
**				can't be installed correctly, return false.
** 
*****************************************************************************/
uint32 SPIInit( void )
{
    TxCounter = 0;

    S0SPCR = 0x00;
    PINSEL0 &= 0xFFFF00FF;
   // PINSEL0 |= 0x00005500;
    PINSEL0 |= 0x00001500;
    IODIR0 = SPI0_SEL;
    IOSET0 = SPI0_SEL;

    /* Setting SPI0 clock, for Atmel SEEPROM, SPI clock should be no more 
    than 3Mhz on 4.5V~5.5V, no more than 2.1Mhz on 2.7V~5.5V */
    S0SPCCR = 0x20;

    S0SPCR = SPI0_MSTR ;//| SPI0_LSBF;

    return( TRUE );
}

/*****************************************************************************
** Function name:		SPISend
**
** Descriptions:		Send a block of data to the SPI port, the first
**				parameter is the buffer pointer, the 2nd 
**				parameter is the block length.
**
** parameters:			buffer pointer, and the block length
** Returned value:		None
** 
*****************************************************************************/
void SPISend( uint8 *buf, uint32 Length )
{
    uint32 i;
    uint8 Dummy;

    if ( Length == 0 )
	return;
    for ( i = 0; i < Length; i++ )
    {
	S0SPDR = *buf;

	while ( !(S0SPSR & SPIF) );

	Dummy = S0SPDR;		/* Flush the RxFIFO */
	buf++;
    }
    return; 
}

/*****************************************************************************
** Function name:		SPIReceive
** Descriptions:		the module will receive a block of data from 
**				the SPI, the 2nd parameter is the block length.
** parameters:			buffer pointer, and block length
** Returned value:		None
** 
*****************************************************************************/
void SPIReceive( uint8 *buf, uint32 Length )
{
    uint32 i;

    for ( i = 0; i < Length; i++ )
    {
	*buf = SPIReceiveuint8();
	buf++;
    }
    return; 
}

/*****************************************************************************
** Function name:		SPIReceiveuint8
**
** Descriptions:		Receive one uint8 of data from the SPI port
**				Write a dummy uint8, wait until SPI transfer
**				complete, then, read the data register to
**				get the SPI data.
**
** parameters:			None
** Returned value:		the data uint8 received
** 
*****************************************************************************/

void writenable(void)
{
	SPICmd[0] = 0x06;
	IOCLR0 = SPI0_SEL;
	
	SPISend(SPICmd,1);
	
	IOSET0 = SPI0_SEL;
}

void writebyte(uint32 addr,uint8 data)
{
	SPICmd[0] = 0x02;
	SPICmd[1] = (addr & 0x00ff0000)>>16;
	SPICmd[2] = (addr & 0x0000ff00)>>16;
	SPICmd[3] = addr & 0x000000ff;
	SPICmd[4] = data;
	//SPICmd[5] = data;
	IOCLR0 = SPI0_SEL;
	SPISend(SPICmd,5);
	IOSET0 = SPI0_SEL;
}

void erase4k(uint32 addr)
{
	SPICmd[0] = 0x20;
	SPICmd[1] = (addr & 0x00ff0000)>>16;
	SPICmd[2] = (addr & 0x0000ff00)>>16;
	SPICmd[3] = addr & 0x000000ff;
	
	IOCLR0 = SPI0_SEL;
	SPISend(SPICmd,4);
	IOSET0 = SPI0_SEL;
}

void unpsec(uint32 addr)
{
	SPICmd[0] = 0x39;
	SPICmd[1] = (addr & 0x00ff0000)>>16;
	SPICmd[2] = (addr & 0x0000ff00)>>16;
	SPICmd[3] = addr & 0x000000ff;
	IOCLR0 = SPI0_SEL;
	
	SPISend(SPICmd,4);
	
	IOSET0 = SPI0_SEL;
}


uint8 readbyte(uint32 addr)
{
	SPICmd[0] = 0x0b;
	SPICmd[1] = (addr & 0x00ff0000)>>16;
	SPICmd[2] = (addr & 0x0000ff00)>>16;
	SPICmd[3] = addr & 0x000000ff;
	SPICmd[4] = 0x00;

	
	IOCLR0 = SPI0_SEL;
	SPISend(SPICmd,5);
	SPIReceive(SPIRDData, 1 );
	IOSET0 = SPI0_SEL;
	return SPIRDData[0];
}


uint8 readstatus(void)
{
	SPICmd[0] = 0x05;
	IOCLR0 = SPI0_SEL;
	
	SPISend(SPICmd,1);
	SPIReceive(SPIRDData, 2 );
	IOSET0 = SPI0_SEL;
	return SPIRDData[0];
}

void wait(void)
{
	
	while(readstatus() & 0x01);
}


uint8 SPIReceiveuint8( void )
{
    uint8 data;

    /* wrtie dummy uint8 out to generate clock, then read data from MISO */
    S0SPDR = 0xFF;
    /* Wait for transfer complete, SPIF bit set */

    while ( !(S0SPSR & SPIF) );

    data = S0SPDR;
    return ( data ); 
}

/******************************************************************************
**                            End Of File
******************************************************************************/