MSP430F249的I2C模块与24CXX连接

1万 · 2018-5-4 15:55

做过用MSP430F249的I2C模块与24CXX连接

1万 · 2018-5-4 16:01

你要例程参考？

1万 · 2018-5-4 16:04

嗯，看看寄存器的配置和时序操作

1万 · 2018-5-4 16:08

你只要写出来iic的驱动，其他的都一样的。

1万 · 2018-5-4 16:13

网上找不到相关的例程，MPS430论坛找好久不见

1万 · 2018-5-4 16:16

两个引脚摸拟的I2C时序会
MSP430F249自带的I2C模块功能不知怎么用，怎么设置

1万 · 2018-5-4 16:22

你安装msp430来找，例程应该都差不多的。

1万 · 2018-5-4 16:27

如果只搜索249资料肯定少的。

1万 · 2018-5-4 16:30

MSP430 系列 IIC模块与24CXX通信的例子很少，
大都是MSP430 IIC模块与其他IC，用中断的多

1万 · 2018-5-4 16:35

24CXX是EEPROM么？这个资料很多的，I2C总线一般用模拟的

1万 · 2018-5-4 16:42

知道了，结贴了

只看该作者 · 2018-5-5 23:16

用的MSP430时, 内部有几十个字节information memory 可以当EEPROM来用

1万 · 2018-5-5 23:17

写驱动程序前要知道i2c协议，eeprom的datasheet，还有相应的引脚图。

2万 · 2018-5-5 23:17

#include <msp430x14x.h>
#include"string.h"
#define SDA_1 P1OUT |= BIT3
#define SDA_0 P1OUT &= ~BIT3
#define SCL_1 P1OUT |= BIT2
#define SCL_0 P1OUT &= ~BIT2
#define SDA_out P1DIR |=BIT3
#define SDA_in P1DIR &= ~BIT3
unsigned char Readword[12];
void init_clk(void)
{
unsigned char j;
BCSCTL1&= ~XT2OFF ;

do
{
      IFG1 &= ~ OFIFG;
      for( j=0xff ; j>0 ; j--)
      {
         _NOP();
      }
}
while((IFG1&OFIFG)!=0);
      BCSCTL2|=SELM_2+SELS;

}
void Delay(void)       //Delay
{
  unsigned char t;
  for(t=0;t<50;t++)
_NOP();
}
void Delay1(void)       //Delay
{
  unsigned char t;
  for(t=0;t<200;t++)
_NOP();
}

void Start(void)       //Start
{
  SDA_out;
  SCL_1;
  _NOP();
SDA_1;
  Delay();
SDA_0;
  Delay();
  SCL_0;
  Delay();
}
void Stop(void)    //Stop
{
  SDA_0;
  Delay();
  SCL_1;
  Delay();
  SDA_1;
  Delay();
}

void ACK(void)       //ACK
{
  SDA_0;
  Delay();
  SCL_1;
  Delay();
  SCL_0;
  Delay();
  SDA_1;
  Delay();

}
void NACK(void)    // NOT ACK
{
  SDA_1;
  Delay();
  SCL_1;
  Delay();
  SCL_0;
  Delay();
  SDA_0;
  Delay();

}

void Write1(void)    //Write a bie : 1
{
  SDA_1;
  Delay();
  SCL_1;
  Delay();
  SCL_0;
  Delay();

}
void Write0(void)          //Write a bit : 0
{
  SDA_0;
  Delay();
  SCL_1;
  Delay();
  SCL_0;
  Delay();

}

void Writebyte(unsigned char Wchar) //Write a byte(8 bit)
{
  unsigned char i;
  for(i=0;i<8;i++)
  {
if(Wchar&0x80) Write1();
else Write0();
Wchar<<=1;
  }
  SDA_1;
  Delay();
}

unsigned char CheckACK(void)  //receive ACK
{
  unsigned char flag;
  //SDA_1;
  Delay();
  SCL_1;
  Delay();
  SDA_in;
  _NOP();_NOP();
  flag = P1IN&BIT3 ;       //read SDA
  SCL_0;
  Delay();
  SDA_out;
  if(flag) return 0;
else return 1;
}

unsigned char Readbyte(void)
{
  unsigned char rchar=0 ,i,flag;

SCL_0;
Delay();
  for(i=0;i<8;i++)
  {
SDA_in;
Delay();
SCL_1;
Delay();
flag=P1IN&BIT3;
   rchar<<=1;
   if(flag) rchar |= 0x01;
_NOP();
SDA_out;
Delay();
SCL_0;
Delay();
  }
   SCL_0;
   Delay();
  return rchar;
}
void  ReadNbyte(unsigned char address,unsigned char dataaddr,unsigned int n)
{
unsigned char i;
   Start();
   Writebyte(address); //find eeprom
   if(!CheckACK())
   {Stop();return ;}
   Writebyte(dataaddr); //find unit address
   if(!CheckACK())
      {Stop();return ;}
   Start();
   Writebyte(0xa1);  //read
   if(!CheckACK())
      {Stop();return ;}

for(i=0;i<n;i++)
{
Readword[i]=Readbyte();
ACK();
}
Stop();
Delay();
}

void WriteNbyte(unsigned char address,unsigned char dataaddr,unsigned char *sbuff,unsigned char n)
{
  unsigned char i;
   Start();
   Writebyte(address); //find eeprom
   if(!CheckACK())
   {Stop();return ;}
   Writebyte(dataaddr); //find unit address
   if(!CheckACK())
      {Stop();return ;}
   for(i=0;i<n;i++)
      {
         Writebyte(sbuff[i]);
         if(!CheckACK())
         {Stop();return ;}
      }
   Stop();
   Delay();

}
void main(void)
{
unsigned char write[9],i;
for(i=0; i<8; i++){
write[i] =49+i;
}

WDTCTL = WDTPW + WDTHOLD;
// init_clk();
P1DIR |= (BIT2 + BIT3);
// P1SEL = 0x0c;                   // P1.2,3 = SCL&SDA
   while(1)
   {
   //write
   WriteNbyte(0xa0,0x00,write,8);
   Delay1();
   //read
   ReadNbyte(0xa0,0x00,8);
   Delay1();Delay1();
   }

}