求助香水STM32 模拟I2C的问题

只看该作者 · 2010-6-8 14:15

网上下了好几个代码，都大同小议，使用起来很不稳定，香水帮忙看下哪里的问题。

我用的I0有所变化，PC9-----WP
                     PC10----SDA
                     PC11----SCL

修改后程序如下：

#include <stm32f10x_lib.h>

bool I2C_FRAM_BufferWrite(u8* pBuffer, u16 WriteAddr, u16 NumByteToWrite);
bool I2C_FRAM_BufferRead(u8* pBuffer, u16 ReadAddr, u16 NumByteToRead);
#define I2C1_SLAVE_ADDRESS7 0xA0
#define I2C_PageSize          256
#define SCL_H       GPIOC->BSRR = GPIO_Pin_11
#define SCL_L       GPIOC->BRR  = GPIO_Pin_11

#define SDA_H       GPIOC->BSRR = GPIO_Pin_10
#define SDA_L       GPIOC->BRR  = GPIO_Pin_10
#define SCL_read    GPIOC->IDR  & GPIO_Pin_11
#define SDA_read    GPIOC->IDR  & GPIO_Pin_10

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
vu8 FRAM_ADDRESS;
/* Private function prototypes -----------------------------------------------*/
/**/
void I2C_delay(void)
{
u8 i=100; //这里可以优化速度       ，经测试最低到5还能写入
while(i)
{
   i--;
}
}
bool I2C_Start(void)
{
      SDA_H;
      SCL_H;
      I2C_delay();
      if(!SDA_read)return FALSE;       //SDA线为低电平则总线忙,退出
      SDA_L;
      I2C_delay();
      if(SDA_read) return FALSE;       //SDA线为高电平则总线出错,退出
      SDA_L;
      I2C_delay();
      return TRUE;
}
void I2C_Stop(void)
{
      SCL_L;
      I2C_delay();
      SDA_L;
      I2C_delay();
      SCL_H;
      I2C_delay();
      SDA_H;
      I2C_delay();
}
void I2C_Ack(void)
{
      SCL_L;
      I2C_delay();
      SDA_L;
      I2C_delay();
      SCL_H;
      I2C_delay();
      SCL_L;
      I2C_delay();
}
void I2C_NoAck(void)
{
      SCL_L;
      I2C_delay();
      SDA_H;
      I2C_delay();
      SCL_H;
      I2C_delay();
      SCL_L;
      I2C_delay();
}
bool I2C_WaitAck(void)       //返回为:=1有ACK,=0无ACK
{
      SCL_L;
      I2C_delay();
      SDA_H;
      I2C_delay();
      SCL_H;
      I2C_delay();
      if(SDA_read)
      {
SCL_L;
return FALSE;
      }
      SCL_L;
      return TRUE;
}
void I2C_SendByte(u8 SendByte) //数据从高位到低位//
{
u8 i=8;
while(i--)
{
      SCL_L;
      I2C_delay();
   if(SendByte&0x80)
      SDA_H;
   else
      SDA_L;
      SendByte<<=1;
      I2C_delay();
            SCL_H;
      I2C_delay();
}
SCL_L;
}
u8 I2C_ReceiveByte(void)  //数据从高位到低位//
{
u8 i=8;
u8 ReceiveByte=0;
SDA_H;
while(i--)
{
   ReceiveByte<<=1;
   SCL_L;
   I2C_delay();
      SCL_H;
   I2C_delay();
   if(SDA_read)
   {
      ReceiveByte|=0x01;
   }
}
SCL_L;
return ReceiveByte;
}

bool WriteFM24C04(u16 WriteAddr, u16 NumByteToWrite, u8 * pBuffer)
{
      u8 Addr = 0, count = 0;
  GPIOC->BRR  = GPIO_Pin_9;//11
      Addr = WriteAddr / I2C_PageSize;
      count = WriteAddr % I2C_PageSize;
      Addr = Addr << 1;
      Addr = Addr & 0x0F;
      FRAM_ADDRESS = I2C1_SLAVE_ADDRESS7 | Addr;
if (!I2C_Start()) return FALSE;
I2C_SendByte(FRAM_ADDRESS);//设置器件地址+段地址
if (!I2C_WaitAck())
      {
            I2C_Stop();
            return FALSE;
      }
I2C_SendByte(count); //设置段内地址
      I2C_WaitAck();

      while(NumByteToWrite--)
      {
      I2C_SendByte(* pBuffer);
      I2C_WaitAck();
   pBuffer++;
      }
      I2C_Stop();
      //注意：因为这里要等待EEPROM写完，可以采用查询或延时方式(10ms)
      //Systick_Delay_1ms(10);
      return TRUE;
}

//读出1串数据
bool ReadFM24C04(u16 WriteAddr,u16 NumByteToRead, u8 * pBuffer)
//bool I2C_FRAM_BufferRead(u8* pBuffer, u16 WriteAddr, u16 NumByteToRead)
{
      u8 Addr = 0, count = 0;
Addr = WriteAddr / I2C_PageSize;
      count = WriteAddr % I2C_PageSize;
      Addr = Addr << 1;
      Addr = Addr & 0x0F;
      FRAM_ADDRESS = I2C1_SLAVE_ADDRESS7 | Addr;

      if (!I2C_Start()) return FALSE;
I2C_SendByte(FRAM_ADDRESS);//设置器件地址+段地址
if (!I2C_WaitAck())
      {
            I2C_Stop();
            return FALSE;
      }
I2C_SendByte(count); //设置低起始地址
I2C_WaitAck();
I2C_Start();
I2C_SendByte(FRAM_ADDRESS | 0x01);
I2C_WaitAck();
while(NumByteToRead)
{
   *pBuffer = I2C_ReceiveByte();
   if(NumByteToRead == 1)I2C_NoAck();
   else I2C_Ack();
   pBuffer++;
   NumByteToRead--;
}
I2C_Stop();
return TRUE;
}