spi_flash.c

基于ATMAL7X256 CS1180的SPI读写FLASH的实例(开发环境ADSv1.2)

#include "include/AT91SAM7X256.h"
#include "include/lib_AT91SAM7X256.h"


//*------------变量定义--------------------------------------------------
static char IsTransfer;
//*------------宏定义-----------------------------------------------------
#define  HighToLow(u32val)  ((u32val &0xFF000000)>>24|(u32val&0x00FF0000)>>8 \
                             |(u32val&0x0000FF00)<<8|(u32val&0x000000FF)<<24)   
//*----------------------------------------------------------------------
//* 函数名称 : __irqSPIHandler
//* 功能描述 : SPI中断服务子函数
//* 入口参数 : 无
//* 出口参数 : 无
//*----------------------------------------------------------------------
__irq void __irqSPIHandler()
{
	
	if(AT91C_BASE_SPI0->SPI_SR & AT91C_SPI_RXBUFF)
	{
		//关闭PDC收发
		AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_RXTDIS|AT91C_PDC_TXTDIS;
		//关SPI中断
		AT91C_BASE_SPI0->SPI_IDR = 0xFFFFFFFF;
		//关闭SPI时钟
		AT91C_BASE_PMC->PMC_PCDR = (unsigned int)0x1<<4;
	
		//设置全局变量
		IsTransfer = 0;
	}
	//向AIC发送中断处理结束
	AT91C_BASE_AIC->AIC_EOICR = 0x1;

}


//*----------------------------------------------------------------------
//* 函数名称 : HardwareInit
//* 功能描述 : 硬件初始化
//* 入口参数 : 无
//* 出口参数 : 无
//*----------------------------------------------------------------------

void HardwareInit(void)
{
	
	//*引脚设置
	//关闭对应中断
	AT91C_BASE_PIOA->PIO_IDR = AT91C_PA16_SPI0_MISO|AT91C_PA17_SPI0_MOSI|AT91C_PA18_SPI0_SPCK;
	//????禁止拉高引脚
	AT91C_BASE_PIOA->PIO_PPUDR = AT91C_PA16_SPI0_MISO|AT91C_PA17_SPI0_MOSI|AT91C_PA18_SPI0_SPCK;

	//选择外设A
	AT91C_BASE_PIOA->PIO_ASR = AT91C_PA16_SPI0_MISO|AT91C_PA17_SPI0_MOSI|AT91C_PA18_SPI0_SPCK;
	//选择复用引脚
	AT91C_BASE_PIOA->PIO_PDR = AT91C_PA16_SPI0_MISO|AT91C_PA17_SPI0_MOSI|AT91C_PA18_SPI0_SPCK;
	//????拉高引脚MISO
	AT91C_BASE_PIOA->PIO_PPUER = AT91C_PA16_SPI0_MISO;
	
	
	//*SPI设置
	//使能SPI时钟
	AT91C_BASE_PMC->PMC_PCER = (unsigned int)1<<4;
	//复位SPI
	AT91C_BASE_SPI0->SPI_CR = AT91C_SPI_SWRST;
	//设置SPI模式
	AT91C_BASE_SPI0->SPI_MR = AT91C_SPI_MSTR|AT91C_SPI_PS_FIXED|AT91C_SPI_MODFDIS;
	//关闭PDC收发
	AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_RXTDIS|AT91C_PDC_TXTDIS;
	//使能SPI
	AT91C_BASE_SPI0->SPI_CR = AT91C_SPI_SPIEN;	
	//关闭SPI时钟
	AT91C_BASE_PMC->PMC_PCDR = (unsigned int)0x1<<4;

	
	//*设置中断
	//注册中断
	AT91F_AIC_ConfigureIt(AT91C_BASE_AIC,
						  4,
						  AT91C_AIC_PRIOR_HIGHEST,
						  AT91C_AIC_SRCTYPE_INT_POSITIVE_EDGE,
						  __irqSPIHandler);
	//关闭SPI中断
	AT91C_BASE_SPI0->SPI_IDR = 0xFFFFFFFF;
	//使能AIC中断
	AT91C_BASE_AIC->AIC_IECR = (unsigned int)0x1<<4;
	
	
	//*flash设置
	//复位flash
	AT91C_BASE_RSTC->RSTC_RMR = 0xA5000000 | (0x09 << 8);
	AT91C_BASE_RSTC->RSTC_RCR = 0xA5000000 | AT91C_RSTC_EXTRST;
	//等待RSTC复位完毕
	while(!(AT91C_BASE_RSTC->RSTC_RSR & AT91C_RSTC_NRSTL));

	//设置片选PIO
	AT91C_BASE_PIOA->PIO_IDR = AT91C_PA12_SPI0_NPCS0;
	AT91C_BASE_PIOA->PIO_PPUDR = AT91C_PA12_SPI0_NPCS0;
	AT91C_BASE_PIOA->PIO_ASR = AT91C_PA12_SPI0_NPCS0;
	AT91C_BASE_PIOA->PIO_PDR = AT91C_PA12_SPI0_NPCS0;
	//设置PCS
	AT91C_BASE_SPI0->SPI_MR |= 0xF0000;
	AT91C_BASE_SPI0->SPI_MR ^= 0x10000;
	//设置为模式3,波特率为1M,片选后延时,连续两次传输延时
	AT91C_BASE_SPI0->SPI_CSR[0] = (unsigned int)0x1 | (unsigned int)0x48<<8 |
								(unsigned int)0x12<<16 | (unsigned int)0x1<<24;

	

}
//*----------------------------------------------------------------------
//* 函数名称 : GetFlashStatus
//* 功能描述 : 获取Flash的状态
//* 入口参数 : 无
//* 出口参数 : unsigned char 状态
//*----------------------------------------------------------------------
void TransferData(unsigned char *OptCode,
				unsigned int OptLength,
				unsigned char *Data,
				unsigned int DataLength)
{
	//开SPI时钟
	AT91C_BASE_PMC->PMC_PCER = (unsigned int)1<<4;
	//关闭PDC收发
	AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_RXTDIS|AT91C_PDC_TXTDIS;
	
	
	//设置PDC
	AT91C_BASE_SPI0->SPI_RPR = OptCode;
	AT91C_BASE_SPI0->SPI_RCR = OptLength;
	AT91C_BASE_SPI0->SPI_TPR = OptCode;
	AT91C_BASE_SPI0->SPI_TCR = OptLength;
	
	AT91C_BASE_SPI0->SPI_RNPR = Data;
	AT91C_BASE_SPI0->SPI_RNCR = DataLength;
	AT91C_BASE_SPI0->SPI_TNPR = Data;
	AT91C_BASE_SPI0->SPI_TNCR = DataLength;
	
	//清中断
	//AT91C_BASE_AIC->AIC_ICCR = (unsigned int)0x1<<4;
	//开SPI中断
	AT91C_BASE_SPI0->SPI_IER = AT91C_SPI_RXBUFF;
	//使能PDC
	AT91C_BASE_SPI0->SPI_PTCR = AT91C_PDC_RXTEN | AT91C_PDC_TXTEN;
}
//*----------------------------------------------------------------------
//* 函数名称 : GetFlashStatus
//* 功能描述 : 获取Flash的状态
//* 入口参数 : 无
//* 出口参数 : unsigned char 状态
//*----------------------------------------------------------------------

unsigned char GetFlashStatus()
{
	unsigned char Status;
	unsigned char Cmd;
	
	Cmd = 0x57;
	
	IsTransfer = 1;
	TransferData(&Cmd,1,&Status,1);
	while(IsTransfer);
	
	return Status;
}
//*----------------------------------------------------------------------
//* 函数名称 : FlashWrite
//* 功能描述 : Flash写函数
//* 入口参数 : 操作的页地址OptPage,操作的位地址OptByte
//*          : 存放数据指针*OptData,数据长度DataLength
//* 出口参数 : 无
//*----------------------------------------------------------------------

void FlashWrite(unsigned short OptPage,
				unsigned short OptByte,
				unsigned char *OptData,
				unsigned int DataLength)
{
	unsigned char status;
	
	//组装操作码
	unsigned int Cmd = 0;
	Cmd = (unsigned int)0x82<<24;
	Cmd |= OptPage<<9;
	Cmd |= OptByte;
	
	Cmd = HighToLow(Cmd);
	
	//传输数据
	IsTransfer = 1;
	TransferData(&Cmd,4,OptData,DataLength);
	while(IsTransfer);
	
	//等待写入结束
	while(1)
	{
		status = GetFlashStatus();
		if(status==(unsigned char)0xA4)
			break;
	}
}
//*----------------------------------------------------------------------
//* 函数名称 : FlashRead
//* 功能描述 : Flash读函数
//* 入口参数 : 操作的页地址OptPage,操作的位地址OptByte
//*          : 存放数据指针*OptData,数据长度DataLength
//* 出口参数 : 无
//*----------------------------------------------------------------------
	
void FlashRead(unsigned short OptPage,
			   unsigned short OptByte,
			   unsigned char *OptData,
			   unsigned int DataLength)
{
	
	//组装操作码
	unsigned int Cmd[2] = {0};

	Cmd[0] = 0x52<<24;
	Cmd[0] |= OptPage<<9;
	Cmd[0] |= OptByte;
	
	Cmd[0] = HighToLow(Cmd[0]);
	
	//传输数据
	IsTransfer = 1;
	TransferData(Cmd,8,OptData,DataLength);
	while(IsTransfer);
	
}
//*----------------------------------------------------------------------
//* 函数名称 : CMain
//* 功能描述 : 主函数
//* 入口参数 : 无
//* 出口参数 : 无
//*----------------------------------------------------------------------

int CMain()
{
	int i;
	unsigned char status;
	unsigned char s[6] = "hello";
	//硬件初始化
	HardwareInit();
	//读取状态
	status = GetFlashStatus();
	//写入数据
	FlashWrite(5,2,s,5);
	status = GetFlashStatus();
	//读出数据
	memset(s,0,5);
	FlashRead(5,2,s,5);
	//读取状态
	status = GetFlashStatus();
	
	
	//*结束后闪灯----------------------
	AT91C_BASE_PIOA->PIO_PER = AT91C_PIO_PA8;
	AT91C_BASE_PIOA->PIO_OER = AT91C_PIO_PA8;
	while(1)
	{
		AT91C_BASE_PIOA->PIO_SODR = AT91C_PIO_PA8;
		for(i=0;i<1000000;i++);
		AT91C_BASE_PIOA->PIO_CODR = AT91C_PIO_PA8;
		for(i=0;i<1000000;i++);
	}
}