求助，PIC24硬件I2C读写AT24HC02，一直收不到ACK信号

只看该作者 · 2013-5-24 23:16

单片机PIC24F256GA108，用的硬件I2C2，发送器件地址后就一直收不到ACK信号了，麻烦高手帮忙看下是什么问题，难道是没初始化好？我I2C初始化就两句话：写BRG寄存器设置速率和将I2CEN位置1，是不是还缺了什么？程序如下：

#define I2C2_Enable()  I2C2CONbits.I2CEN = 1
#define I2C2_Disable()  I2C2CONbits.I2CEN = 0
#define I2C2_SetBRG(BRG)  I2C2BRG = BRG
#define I2C2_Start()  I2C2CONbits.SEN = 1;while(I2C2CONbits.SEN)
#define I2C2_Restart()  I2C2CONbits.SEN = 1;while(I2C2CONbits.SEN)
#define I2C2_Stop()  I2C2CONbits.PEN = 1;while(I2C2CONbits.PEN)
#define I2C2_Idle()  while(/*I2C2CON & 0x1f*/ I2C2STATbits.TRSTAT);
#define I2C2_GetAck()  while(!I2C2STATbits.ACKSTAT);
#define I2C2_GetNack()  while(I2C2STATbits.ACKSTAT);
#define I2C2_SendAck()  I2C2CONbits.ACKDT = 0;I2C2CONbits.ACKEN = 1;while(I2C2CONbits.ACKEN)
#define I2C2_SendNack()  I2C2CONbits.ACKDT = 1;I2C2CONbits.ACKEN = 1;while(I2C2CONbits.ACKEN)

void I2C2_Init()
{
I2C2BRG = 0x004e;
I2C2CON = 0x1000;
}

void I2C2_Write(uint8_t byte)
{
I2C2TRN = byte;
while (I2C2STATbits.TBF);
}

uint8_t I2C2_Read()
{
uint8_t byte;
I2C2CONbits.RCEN = 1;
while(I2C2STATbits.RBF);
byte = I2C2RCV;
return byte;
}

void Eeprom_Init()
{
I2C2_Init();
}

void Eeprom_Write(uint8_t Device_Addr,uint8_t Data_Addr,uint8_t Data)
{
I2C2_Start();
I2C2_Idle();

I2C2_Write(Device_Addr);
I2C2_Idle();
I2C2_GetAck();

I2C2_Write(Data_Addr);
I2C2_Idle();
I2C2_GetAck();

I2C2_Write(Data);
I2C2_Idle();
I2C2_GetAck();

I2C2_Stop();
I2C2_Idle();
}

uint8_t Eeprom_Read(uint8_t Device_Addr,uint8_t Data_Addr)
{
uint8_t byte;

I2C2_Start();
I2C2_Idle();

I2C2_Write(Device_Addr);
I2C2_Idle();
I2C2_GetAck();

I2C2_Write(Data_Addr);
I2C2_Idle();
I2C2_GetAck();

I2C2_Restart();
I2C2_Idle();

I2C2_Write(Device_Addr | 0x01);
I2C2_Idle();
I2C2_GetAck();

byte = I2C2_Read();
I2C2_SendNack();

I2C2_Stop();
I2C2_Idle();

return byte;
}

发送完器件地址后就一直停在了I2C2_GetAck() 即 while(!I2C2STATbits.ACKSTAT)处。