//===================================================================
// SMDK2440 IIC configuration
// GPE15=IICSDA, GPE14=IICSCL
// "Non-Interrupt" mode for IIC block
//===================================================================
//*********************[ Test_Iic2 ]*********************************
void Test_Iic2(void)
{
unsigned int i,j,save_E,save_PE;
static U8 data[256];
Uart_Printf("[ IIC Test(Polling) using KS24C080 ]\n");
save_E = rGPECON;
save_PE = rGPEUP;
rGPEUP |= 0xc000; //Pull-up disable
rGPECON |= 0xa00000; //GPE15:IICSDA , GPE14:IICSCL(应改为0xa0000000)
//Enable ACK, Prescaler IICCLK=PCLK/16, Enable interrupt, Transmit clock value Tx clock=IICCLK/16
rIICCON = (1<<7) | (0<<6) | (1<<5) | (0xf);
rIICADD = 0x10; //2440 slave address = [7:1]
rIICSTAT = 0x10; //IIC bus data output enable(Rx/Tx)
//rIICLC = (1<<2)|(3); // Filter enable, 15 clocks SDA output delay added by junon
Uart_Printf("Write test data into KS24C080\n");
for(i=0;i<256;i++)
_Wr24C080(0xa0,(U8)i,255-i);
for(i=0;i<256;i++)
data[i] = 0;
Uart_Printf("Read test data from KS24C080\n");
for(i=0;i<256;i++)
_Rd24C080(0xa0,(U8)i,&(data[i]));
for(i=0;i<16;i++)
{
for(j=0;j<16;j++)
Uart_Printf("%2x ",data[i*16+j]);
Uart_Printf("\n");
}
rGPEUP = save_PE;
rGPECON = save_E;
}
//**************[ _Wr24C080 ]*****************************************
void _Wr24C080(U32 slvAddr,U32 addr,U8 data)
{
_iicMode = WRDATA; //设置为写数据模式
_iicPt = 0; //IIC指针指向0地址
_iicData[0] = (U8)addr; //给Data数组的0元素赋值,内部地址
_iicData[1] = data; //给Data数组的1元素赋值,写入的数据
_iicDataCount = 2; //数据计数初始值为2
rIICDS = slvAddr; //0xa0 把从机设备地址给IICDS
//Master Tx mode, Start(Write), IIC-bus data output enable设置为主发送模式，写IIC产生开始信号，使能RX/TX
//Bus arbitration sucessful, Address as slave status flag Cleared,
//Address zero status flag cleared, Last received bit is 0
rIICSTAT = 0xf0;
//Clearing the pending bit isn't needed because the pending bit has been cleared.
while(_iicDataCount!=-1)
Run_IicPoll();
_iicMode = POLLACK;
while(1)
{
rIICDS = slvAddr;
_iicStatus = 0x100; //To check if _iicStatus is changed
rIICSTAT = 0xf0; //Master Tx, Start, Output Enable, Sucessful, Cleared, Cleared, 0
rIICCON = 0xaf; //Resumes IIC operation.
while(_iicStatus==0x100)
Run_IicPoll();
if(!(_iicStatus & 0x1))
break; //When ACK is received
}
rIICSTAT = 0xd0; //Master Tx condition, Stop(Write), Output Enable
rIICCON = 0xaf; //Resumes IIC operation.
Delay(1); //Wait until stop condtion is in effect.
//Write is completed.
}
//************************[ _Rd24C080 ]********************************
void _Rd24C080(U32 slvAddr,U32 addr,U8 *data)
{
_iicMode = SETRDADDR;
_iicPt = 0;
_iicData[0] = (U8)addr;
_iicDataCount = 1;
rIICDS = slvAddr;
rIICSTAT = 0xf0; //MasTx,Start
//Clearing the pending bit isn't needed because the pending bit has been cleared.
while(_iicDataCount!=-1)
Run_IicPoll();
_iicMode = RDDATA;
_iicPt = 0;
_iicDataCount = 1;
rIICDS = slvAddr;
rIICSTAT = 0xb0; //Master Rx,Start
rIICCON = 0xaf; //Resumes IIC operation.
while(_iicDataCount!=-1)
Run_IicPoll();
*data = _iicData[1];
}
//**********************[ Run_IicPoll ]*********************************
//该函数的作用就是判断一个字节是否发送或者接收完毕，因为已经说明了，只要传
输完毕，就会产生中断，使 IIC 控制寄存器的 bit4 置 1。该函数判断该位，如果
为1，说明传输完毕，可以进行下面的字节传输，如果是 0，则继续等待，直到它变
为1。如果变为1，就调用IicPoll 函数。
//********************************************************************//
void Run_IicPoll(void)
{
if(rIICCON & 0x10)
IicPoll();
}
//**********************[IicPoll ]**************************************
//该函数的主体是一个 switch 语句，用来判断现在进行的是什么操作，并进行
相应的读写操作。这个函数主要反映了 I2C 的时序
//***********************************************************************//
void IicPoll(void)
{
U32 iicSt,i;
iicSt = rIICSTAT;
if(iicSt & 0x8){} //When bus arbitration is failed.
if(iicSt & 0x4){} //When a slave address is matched with IICADD
if(iicSt & 0x2){} //When a slave address is 0000000b
if(iicSt & 0x1){} //When ACK isn't received
switch(_iicMode)
{
case POLLACK:
_iicStatus = iicSt;
break;
case RDDATA:
if((_iicDataCount--)==0)
{
_iicData[_iicPt++] = rIICDS;
rIICSTAT = 0x90; //Stop MasRx condition
rIICCON = 0xaf; //Resumes IIC operation.
Delay(1); //Wait until stop condtion is in effect.
//Too long time...
//The pending bit will not be set after issuing stop condition.
break;
}
_iicData[_iicPt++] = rIICDS;
//The last data has to be read with no ack.
if((_iicDataCount)==0)
rIICCON = 0x2f; //Resumes IIC operation with NOACK.
else
rIICCON = 0xaf; //Resumes IIC operation with ACK
break;
case WRDATA:
if((_iicDataCount--)==0)
{
rIICSTAT = 0xd0; //stop MasTx condition
rIICCON = 0xaf; //resumes IIC operation
Delay(1); //wait until stop condtion is in effect.
//The pending bit will not be set after issuing stop condition.
break;
}
rIICDS = _iicData[_iicPt++]; //_iicData[0] has dummy.
for(i=0;i<10;i++); //for setup time until rising edge of IICSCL
rIICCON = 0xaf; //resumes IIC operation.
break;
case SETRDADDR:
// Uart_Printf("[S%d]",_iicDataCount);
if((_iicDataCount--)==0)
{
break; //IIC operation is stopped because of IICCON[4]
}
rIICDS = _iicData[_iicPt++];
for(i=0;i<10;i++); //for setup time until rising edge of IICSCL
rIICCON = 0xaf; //resumes IIC operation.
break;
default:
break;
}
}
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