S3C2410 IIC interface analyse

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S3C2410 IIC interface analyse
  From the manual,we know that the following steps should be executed before any IIC Rx/Tx operations:
1)write slave device address to IICADD register,if needed.
2)configure IICCON register,enable interrupt and define SCL period
3)configure IICSTAT register,enable serial output
1.Operations for slave receiver mode
1)IICADD=0xaa;  //the slave device address
2)IICCON=0xe2; //enable ACK,(Tx Clock)IICCLK=Fpclk/512,enable interrupt
3)IICSTAT=0x10; //slave receive mode,enable serial output
4)wait for IIC receive interrupt signal
5)enter interrupt handle function
6)uint8_t tmp=IICDS & 0xff; //read data
7)IICCON &= 0xef; //clean pending and resume
2.Operations for slave transmitter mode
1)IICADD=0xaa; //the slave device address
2)IICCON=0xe2; //enable ACK,(Tx Clock)IICCLK=Fpclk/512,enable interrupt
3)IICSTAT=0x50; //slave transmit mode,enable serial output
4)wait for IIC receive interrupt signal
5)enter interrupt handle function
6)IICDS=tmp;   //send data
7)IICCON &= 0xef; //clean pending and resume
3.Operations for master receiver mode
1)IICCON=0xe2; //enable ACK,(Tx Clock)IICCLK=Fpclk/512,enable interrupt
2)IICSTAT=0x90; //master receive mode,enable serial output
3)IICDS=0xaa;   //write slave device address
4)IICSTAT=0xb0; //why?[5]This bit stands for START signal generation,when 1,the data in IICDS will be transfered
automatically just after the start signal.
5)//enter ACK period,read ACK,then interrupt is pending
6)uint8_t tmp= IICDS & 0xff; //read data
7)IICCON &= 0xef; //clean pending and resume
8)IICSTAT=0x90; //why?[5] when write 0 will generate STOP signal.
4.Operations for master transmitter mode
1)IICCON=0xe2; //enable ACK,(Tx Clock)IICCLK=Fpclk/512,enable interrupt
2)IICSTAT=0xd0; //master receive mode,enable serial output
3)IICDS=0xaa;   //write slave device address
4)IICSTAT=0xf0; //START signal
5)//enter ACK period,read ACK,then interrupt is pending
6)IICDS=tmp; //write new data
7)IICCON &= 0xef; //clean pending and resume
8)IICSTAT=0xd0; //STOP signal

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