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本帖最后由 Lu.Shi 于 2013-11-6 16:24 编辑
我自己使用dsPIC33E单片机往25LC256里面读写数据，但是感觉SPI2BUF写不进去数据。
具体的代码如下：
SPI.c函数:
static void Spi_vSpi2SetPin(void)
{
/*Chose SPI2: so SDI2 - RG7, SDO2 - RG8*/
TRISGbits.TRISG7 = 1; /*RG7 - input*/
TRISGbits.TRISG8 = 0; /*RG8 - output*/
/*use RD12 for CS signal*/
TRISDbits.TRISD12 = 0; /*RD12 - output*/
return;
}
static void Spi_vSpi2Write(unsigned char Data)
{
SPI2BUF = Data & 0xff;
while(SPI2STATbits.SPITBF);
Data = SPI2BUF; /*avoiding overflow when reading*/
return;
}
static unsigned char Spi_u8Spi2Read(void)
{
unsigned char Data=0;
SPI2STATbits.SPIROV = 0;
while(!SPI2STATbits.SPIRBF);/* Check for Receive buffer full status bit of status register*/
if (SPI2STATbits.SPIRBF)
{
SPI2STATbits.SPIROV = 0;
Data = SPI2BUF;
}
return(Data);
}
void Spi_vSpi2Initial(void)
{
Spi_vSpi2SetPin();
/*intial SPI2STAT SFR*/
SPI2STATbits.SPIEN = 0; /*bits 15:disable SPI*/
SPI2STATbits.SPISIDL = 0; /*bit 13:still work in free mode*/
SPI2STATbits.SPIBEC = 0;/*bit 10-8:it will work in ESPI*/
SPI2STATbits.SRMPT = 0;/*bit 7:it will work in ESPI*/
SPI2STATbits.SPIROV = 0;/*bit 6:ont receive Ooerflow*/
SPI2STATbits.SRXMPT = 0;/*bits 5:it will work in ESPI*/
SPI2STATbits.SISEL = 0;/*bit 4-2:it will work in ESPI*/
SPI2STATbits.SPITBF = 0; /*bit 1:auto set or clear by hardware*/
SPI2STATbits.SPIRBF = 0;/*bit 0:auto set or clear by hardware*/
/*initial SPI2CON1 SFR*/
SPI2CON1bits.DISSCK = 0;/*bit 12: use internal SPI clock*/
SPI2CON1bits.DISSDO = 0;/*bit 11:SDO2 control by SPI*/
SPI2CON1bits.MODE16 = 0;/*bit 10:communication by 8 bits*/
SPI2CON1bits.SMP = 0;/*bit 9:input data during data output*/
SPI2CON1bits.CKE = 1;/*bit 8:change data when mode from work to free*/
SPI2CON1bits.SSEN = 0;/*bit 7:SSx control by SPI*/
SPI2CON1bits.CKP = 0;/*bit 6:work - high level;free - low level*/
SPI2CON1bits.MSTEN = 1;/*bit 5:enable Master mode*/
/*Fsck = Fcy/(SPRE * PPRE), Fsck = 30MHz/(3*4) = 2.5MHz*/
SPI2CON1bits.SPRE = 5;/*bit 4-2:Auxiliary preassigned frequency 3:1*/
SPI2CON1bits.PPRE = 2;/*bit 1-0:preassigned frequency 4:1*/
/*initial SPI2CON2 SFR*/
SPI2CON2bits.FRMEN = 0;/*bit 15:disable SPIx frame mode*/
SPI2CON2bits.SPIFSD = 0;/*bit 14:Frame synchronization pulse output*/
SPI2CON2bits.FRMPOL = 0;/*bit 13:Frame synchronization pulse low level*/
SPI2CON2bits.FRMDLY = 0;/*bit 1:use the same clock */
SPI2CON2bits.FRMEN = 0;/*bit 0:use standed mode*/
/*set input and output pins*/
RPOR14bits.RP120R = 8;
RPOR13bits.RP118R = 9; /*SCK2 to G6*/
SPI2STATbits.SPIEN = 1; /*bits 15:enable SPI*/
}
void Spi_vSpi2WriteEnable(void)
{
LATDbits.LATD12 = 0;
Spi_vSpi2Write(SPI_WRITE_EN_COMMAND);
LATDbits.LATD12 = 1;
return;
}
void Spi_vSpi2WriteCheck(void)
{
unsigned char Status;
do
{
LATDbits.LATD12 = 0;
Spi_vSpi2Write(SPI_READ_SR_COMMAND); /*Read STATUS Register command*/
Status = Spi_u8Spi2Read(); /*Read STATUS Register*/
LATDbits.LATD12 = 1;
} while (Status & 0x01);
}
void Spi_vSpi2WriteStatusReg(unsigned char StatusData)
{
LATDbits.LATD12 = 0;
Spi_vSpi2Write(SPI_WRITE_SR_COMMAND);
Spi_vSpi2Write(StatusData);
LATDbits.LATD12 = 1;
return;
}
void Spi_vSpi2WriteByte(unsigned char AddressH,unsigned char AddressL,unsigned char Data)
{
Spi_vSpi2WriteCheck();
LATDbits.LATD12 = 0;
/*send BTTE WRITE SEQUENCE command*/
Spi_vSpi2Write(SPI_WRITE_COMMAND);
/*write address:16 bits*/
Spi_vSpi2Write(AddressH);/*send AddressH*/
Spi_vSpi2Write(AddressL);/*send AddressL*/
/*write data*/
Spi_vSpi2Write(Data);
LATDbits.LATD12 = 1;
Spi_vSpi2WriteCheck();
return;
}
unsigned char Spi_u8Spi2ReadSequence(unsigned char AddressH,unsigned char AddressL)
{
static unsigned char Data;
LATDbits.LATD12 = 0;
/*send write READ SEQUENCE command*/
Spi_vSpi2Write(SPI_READ_COMMAND);
/*write READ DATA address*/
Spi_vSpi2Write(AddressH);/*send AddressH*/
Spi_vSpi2Write(AddressL);/*send AddressL*/
/*read data*/
Data = Spi_u8Spi2Read();
LATDbits.LATD12 = 1;
return(Data);
}
Main.c函数：
void InitPorts(void)
{
TRISA = 0x0000;
LATA = 0x00FF; /*LED is all ON*/
}
void delay(void)
{
unsigned int i,j;
for(i=0;i<3000;i++)
{
for(j=0;j<3000;j++)
;
}
}
int main(void)
{
PLLFBD = 0x003A;
CLKDIV = 0x0040;
InitPorts();
delay();
delay();
Spi_vSpi2Initial();
while(1)
{
Spi_vSpi2WriteEnable();
Spi_vSpi2WriteByte(0x01,0x03,0x01);
LATA = Spi_u8Spi2ReadSequence(0x01,0x03);
delay();
delay();
}
}
然后把程序烧板子里面会出现LED先全亮一会（初始化全亮然后有delay延时），然后全灭，说明通过SPI读到的数据为0，但是往相同地址写数据了，只有可能是没写进去，然后我连着板子在线调试了，程序会停在 Spi_vSpi2Write（）函数的while循环，但是按照datasheet的说明while判断没有问题，那就是数据写不进SPI2BUF，但是为什么会写不进去呢？？
希望各位牛人给点建议和意见，在此表示非常感谢！！！！ |
阿莫论坛20周年了！感谢大家的支持与爱护！！
曾经有一段真挚的爱情摆在我的面前，我没有珍惜，现在想起来，还好我没有珍惜……
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发表于 2013-11-6 16:11:03
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