lpc_spi.c

NXP ARM7 用SPI 接口 驱动铁电FM25256

// Filename: lpc_spi.c
// Author:   Zhang Sheng
// Orgnize:  Estun digital technology
// Revision  Modifier  Data
// xxx       xxx       xxx
// Function: 
// LPC ARM7 SPI1 驱动，和对FM25256的操作

#include "lpc_spi.h"

// SPI的设置，在系统初始化时调用
void SPI_Init(unsigned char fdiv)
{
  //使能SPI1功能
  /*
  P0_FUN2(20);	//SSEL
  P0_FUN2(19);	//MOSI
	P0_FUN2(18);	//MISO
	P0_FUN2(17);	//SCLK
	P2_DIROUT(18);//CS
	P2_SET(18);		//
  */
  if(fdiv < 8)
    fdiv = 8;
  S1SPCCR = fdiv & 0xfe;
  S1SPCR = SPI_MODE;
#if (SPI_MODE & SPCR_SPIE)
#define SPI_Int_Enable
#endif
}

// 向SPI写一个字节数据
void SPI_Write(unsigned char data)
{
  //SPI_CS_CLR;//片选
  S1SPDR = data;
  while(0 == (S1SPSR & SPSR_SPIF));
  //SPI_CS_SET;
}

// 从SPI读数据
unsigned char SPI_Read(void)
{
  return (S1SPDR);
}

// 清除SPI中断标志
void SPI_ClrInt(void)
{
#ifdef SPI_Int_Enable
  S1SPINT |= SPINT_IF;
#endif
}

// 写两个字节数据
void write_uint16(unsigned short data)
{
  unsigned char tmp;
  tmp = (unsigned char)(data & 0xff);
  SPI_Write(tmp);
  tmp = (unsigned char)(data>>8);
  SPI_Write(tmp);
}

// 写四个字节数据
void write_uint32(unsigned int data)
{
  unsigned char tmp;
  tmp = (unsigned char)(data & 0xff);
  SPI_Write(tmp);
  data = data >> 8;
  tmp = (unsigned char)(data & 0xff);
  SPI_Write(tmp);
  data = data >> 8;
  tmp = (unsigned char)(data & 0xff);
  SPI_Write(tmp);
  data = data >> 8;
  tmp = (unsigned char)(data & 0xff);
  SPI_Write(tmp);
}

//set write enable latch
void wren(void)
{
  SPI_CS_CLR;//片选
  SPI_Write(FM_WREN);
  SPI_CS_SET;
}

//write status register
void wrsr(unsigned char protect_byte)
{
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_WRSR);
  SPI_Write(protect_byte);
  //__enable_interrupt();
  SPI_CS_SET;
}

//write disable
void wrdi(void)
{
  SPI_CS_CLR;//片选
  SPI_Write(FM_WRDI);
  SPI_CS_SET;
}

//read status register
unsigned char rdsr(void)
{
  unsigned char tmp = 0;
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_RDSR);
  SPI_Write(FM_RDSR);//For waitting.
  tmp = SPI_Read();
  //__enable_interrupt();
  SPI_CS_SET;
  return tmp;
}

//write   add bewteen 0000 and 7FFF.
//This add bewteen 000 and 7fff.
void write(unsigned short address,unsigned char indata)
{
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_WRITE);
  write_uint16(address);
  SPI_Write(indata);
  //__enable_interrupt();
  SPI_CS_SET;
}

//write
//This add bewteen 0000 and 7Fff.
void fm_write(unsigned short address, unsigned char fm_data)
{
   wren();
   write(address, fm_data);
   wrdi();
}

//  写连续的数据 （地址自动递增）
//  add bewteen 0000 and 7FFF
void fm_seqWrite(unsigned short address,unsigned char *pArray,unsigned short n)
{
  unsigned short i;
  
  wren();    
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_WRITE);
  write_uint16(address);
  for (i = 0;i < n;i++)
  {
    SPI_Write(*pArray++);
  }
  //__enable_interrupt();
  SPI_CS_SET;
  wrdi();
}

//read a byte
//This add bewteen 0000 and 7Fff.
unsigned char fm_read(unsigned short address)
{
  unsigned char tmp;
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_READ);
  write_uint16(address);
  SPI_Write(0xff);//For waitting.
  tmp = SPI_Read();
  //__enable_interrupt();
  SPI_CS_SET;
  return tmp;
}

//  读连续的数据 （地址自动递增）
//  add bewteen 0000 and 7FFF
void fm_seqread(unsigned short address,unsigned short n,unsigned char *pp)
{
  unsigned short i;
  
  SPI_CS_CLR;//片选
  //__disable_interrupt();
  SPI_Write(FM_READ);
  write_uint16(address);
  for (i=0; i<n; i++)
  {
    SPI_Write(0xff);//For waitting.
    *pp  = SPI_Read();
    ++pp;
  }
  //__enable_interrupt();
  SPI_CS_SET;
}