STC32G128K硬件I2C输出波形异常
我用的MCU（STC32G12K128)的I2C模块，当SDA输出start信号（拉低）后，会有一个拉高的时间，然后在拉低。导致与IC通讯不上，不知道是什么原因代码如下
#include"I2C.h"
#include <intrins.h>
#define SOFT_I2C_SCL P25
#define SOFT_I2C_SDA P24
u8 const CRC8Table[]=
{
0x00,0x07,0x0E,0x09,0x1C,0x1B,0x12,0x15,0x38,0x3F,0x36,0x31,0x24,0x23,0x2A,0x2D,
0x70,0x77,0x7E,0x79,0x6C,0x6B,0x62,0x65,0x48,0x4F,0x46,0x41,0x54,0x53,0x5A,0x5D,
0xE0,0xE7,0xEE,0xE9,0xFC,0xFB,0xF2,0xF5,0xD8,0xDF,0xD6,0xD1,0xC4,0xC3,0xCA,0xCD,
0x90,0x97,0x9E,0x99,0x8C,0x8B,0x82,0x85,0xA8,0xAF,0xA6,0xA1,0xB4,0xB3,0xBA,0xBD,
0xC7,0xC0,0xC9,0xCE,0xDB,0xDC,0xD5,0xD2,0xFF,0xF8,0xF1,0xF6,0xE3,0xE4,0xED,0xEA,
0xB7,0xB0,0xB9,0xBE,0xAB,0xAC,0xA5,0xA2,0x8F,0x88,0x81,0x86,0x93,0x94,0x9D,0x9A,
0x27,0x20,0x29,0x2E,0x3B,0x3C,0x35,0x32,0x1F,0x18,0x11,0x16,0x03,0x04,0x0D,0x0A,
0x57,0x50,0x59,0x5E,0x4B,0x4C,0x45,0x42,0x6F,0x68,0x61,0x66,0x73,0x74,0x7D,0x7A,
0x89,0x8E,0x87,0x80,0x95,0x92,0x9B,0x9C,0xB1,0xB6,0xBF,0xB8,0xAD,0xAA,0xA3,0xA4,
0xF9,0xFE,0xF7,0xF0,0xE5,0xE2,0xEB,0xEC,0xC1,0xC6,0xCF,0xC8,0xDD,0xDA,0xD3,0xD4,
0x69,0x6E,0x67,0x60,0x75,0x72,0x7B,0x7C,0x51,0x56,0x5F,0x58,0x4D,0x4A,0x43,0x44,
0x19,0x1E,0x17,0x10,0x05,0x02,0x0B,0x0C,0x21,0x26,0x2F,0x28,0x3D,0x3A,0x33,0x34,
0x4E,0x49,0x40,0x47,0x52,0x55,0x5C,0x5B,0x76,0x71,0x78,0x7F,0x6A,0x6D,0x64,0x63,
0x3E,0x39,0x30,0x37,0x22,0x25,0x2C,0x2B,0x06,0x01,0x08,0x0F,0x1A,0x1D,0x14,0x13,
0xAE,0xA9,0xA0,0xA7,0xB2,0xB5,0xBC,0xBB,0x96,0x91,0x98,0x9F,0x8A,0x8D,0x84,0x83,
0xDE,0xD9,0xD0,0xD7,0xC2,0xC5,0xCC,0xCB,0xE6,0xE1,0xE8,0xEF,0xFA,0xFD,0xF4,0xF3
};
u16I2C_StateFlowUW;
u8 I2C_DeviceAdrrUB;
u8 I2C_DeviceRegAddrUB;
u8 I2C_DeviceRegDtUB;
u8 I2C_crcResUB;
u16I2C_DeviceDtRtUW;
u8 I2C_hdAckUB;
u8 I2C_stWrkStUB;
I2C_wtFifo_S I2C_wtDeviceBuf;
I2C_rdFifo_S I2C_deviceBackBuf;
voidI2C_EnterLowPowerMode(void)
{
// stop all I2C communication
for(;;)
{
I2C_Update();
}
}
voidI2C_RecoveryFromLowPowerMode(void)
{
}
/*******************************************************************************
Function: CRC8cal()
Description:
Input:
Output:
********************************************************************************/
u8 CRC8cal(u8 *p, u8 counter) //look-up table calculte CRC
{
u8 crc8 = 0;
for( ; counter > 0; counter--)
{
crc8 = CRC8Table;
p++;
}
return (crc8);
}
/*******************************************************************************
Function: I2C_Init()
Description:
Input:
Output:
********************************************************************************/
void I2C_Init(void)
{
P2M0 &= 0xCF;
P2M1 &= 0xCF;
P2PU |= 0x30;
P_SW2 |= 0x90; // i2c mirror to P3.2 P3.3; extern ram aera allow
I2CCFG = 0xdc;// ENABLE I2C; MASTER MODE; 200K RATE
I2CMSAUX = 0; // DISABLE MASTER MODE AUTO SEND ACK
I2CMSST = 0;
I2C_StateFlowUW = 0;
I2C_wtDeviceBuf.wP = 0;
I2C_wtDeviceBuf.rP = 0;
I2C_deviceBackBuf.wP = 0;
I2C_deviceBackBuf.rP = 0;
I2CMSCR = 0;
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_SetSlaveAddr(u8 addrUB)
{
I2C_DeviceAdrrUB = addrUB;
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_SendData(u8datUB)
{
I2CTXD = datUB;
I2CMSCR = 0x2;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_StartProc(void)
{
I2CMSCR = 0x1;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_ReadAck(void)
{
I2CMSCR = 0x3;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_RecvData(void)
{
I2CMSCR = 0x4;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_SendAck(u8 ackBool)
{
if(ackBool == 1)
{
I2CMSST |= 1;
}
else
{
I2CMSST &= 0xfe;
}
I2CMSCR = 0x5;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_SendStop(void)
{
I2CMSCR = 0x6;
for(;;)
{
if((I2CMSST & 0x40 ) == 0x40)
{
I2CMSST &= ~0x40;
break;
}
}
}
/*******************************************************************************
// write data to slave device
********************************************************************************/
voidI2C_WriteDeviceBuf(u8 regAddr, u8 dtUB , u8 rdOrWt)
{
u8 idxWtUB;
if((I2C_wtDeviceBuf.wP + 1)%_I2C_WRITE_BUF_SIZE_ != I2C_wtDeviceBuf.rP)
{
idxWtUB = I2C_wtDeviceBuf.wP;
I2C_wtDeviceBuf.addrUB = regAddr;
I2C_wtDeviceBuf.dtUB = dtUB;
I2C_wtDeviceBuf.rwflg = rdOrWt;
I2C_wtDeviceBuf.wP= (u8)((I2C_wtDeviceBuf.wP+ 1)%_I2C_WRITE_BUF_SIZE_);
}
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_WriteDeviceBack(u8 regAddr , u16 back)
{
u8 idxWtUB;
if((I2C_deviceBackBuf.wP + 1)%_I2C_READ_BUF_SIZE_ != I2C_deviceBackBuf.rP)
{
idxWtUB = I2C_deviceBackBuf.wP;
I2C_deviceBackBuf.addrUB = regAddr;
I2C_deviceBackBuf.dtUW = back;
I2C_deviceBackBuf.wP= (u8)((I2C_deviceBackBuf.wP+ 1)%_I2C_READ_BUF_SIZE_);
}
}
/*******************************************************************************
//
********************************************************************************/
u16I2C_ReadDeviceBackBuf(u8* regAddr)
{
u16 retUW;
if(I2C_deviceBackBuf.wP != I2C_deviceBackBuf.rP)
{
*regAddr = I2C_deviceBackBuf.addrUB;
retUW = I2C_deviceBackBuf.dtUW;
I2C_deviceBackBuf.rP = (u8)((I2C_deviceBackBuf.rP + 1)%_I2C_READ_BUF_SIZE_);
}
else
{
*regAddr = 0xff;
retUW = 0xffff;
}
returnretUW;
}
/*******************************************************************************
//
********************************************************************************/
voidI2C_Update(void)
{
static u8 TempBuf;
u8 rdBuf , crcBack ;
if((I2C_wtDeviceBuf.wP != I2C_wtDeviceBuf.rP)&&(I2C_StateFlowUW == 0)&&((I2CMSST & 0x80 ) == 0))
{
rdBuf = I2C_wtDeviceBuf.rP;
I2C_DeviceRegAddrUB = I2C_wtDeviceBuf.addrUB;
I2C_DeviceRegDtUB = I2C_wtDeviceBuf.dtUB;
// write 4 byte ( I2C_DeviceAdrrUB , I2C_DeviceRegAddrUB , I2C_DeviceRegDtUB , I2C_crcResUB ) to
// slave device -- SH367306
TempBuf = I2C_DeviceAdrrUB;
TempBuf = I2C_DeviceRegAddrUB;
if(I2C_wtDeviceBuf.rwflg == 0) // write to SH367306
{
TempBuf = I2C_DeviceRegDtUB;
I2C_crcResUB = CRC8cal(TempBuf, 3);
I2C_StateFlowUW = 0x8000;
I2C_StartProc();
I2C_SendData(I2C_DeviceAdrrUB);
I2C_StateFlowUW |= 0x01;
}
if(I2C_wtDeviceBuf.rwflg == 1) // read from SH367306
{
I2C_DeviceDtRtUW = 0;
TempBuf = I2C_DeviceAdrrUB | 0x01;
I2C_StateFlowUW = 0x4000;
I2C_StartProc();
I2C_SendData(I2C_DeviceAdrrUB);
I2C_StateFlowUW |= 0x01;
}
I2C_wtDeviceBuf.rP = (u8)((I2C_wtDeviceBuf.rP + 1)%_I2C_WRITE_BUF_SIZE_);
}
if((I2C_StateFlowUW &0x8000) == 0x8000) // write device -- SH367306
{
// STEP 9
if(I2C_StateFlowUW == 0x80ff)//send stop
{
I2C_SendStop();
I2C_StateFlowUW = 0;
}
// STEP 8
if(I2C_StateFlowUW == 0x807f)//wait second ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x80;
}
// STEP 7
if(I2C_StateFlowUW == 0x803f)//write SH367306 CRC
{
I2C_SendData(I2C_crcResUB);
I2C_StateFlowUW |= 0x40;
}
// STEP 6
if(I2C_StateFlowUW == 0x801f)//wait second ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x20;
}
// STEP 5
if(I2C_StateFlowUW == 0x800f)//write SH367306 register data
{
I2C_SendData(I2C_DeviceRegDtUB);
I2C_StateFlowUW |= 0x10;
}
// STEP 4
if(I2C_StateFlowUW == 0x8007)//wait second ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x08;
}
// STEP 3
if(I2C_StateFlowUW == 0x8003)// write SH367306 register address
{
I2C_SendData(I2C_DeviceRegAddrUB);
I2C_StateFlowUW |= 0x04;
}
// STEP 2
if(I2C_StateFlowUW== 0x8001)// wait first ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x02;
}
}
if((I2C_StateFlowUW &0x4000) == 0x4000) // read SH367306
{
// STEP 14
if(I2C_StateFlowUW == 0x7fff)//send stop
{
I2C_SendStop();
I2C_StateFlowUW = 0;
}
// STEP 14
if(I2C_StateFlowUW == 0x5fff)// read low byte of word register from SH367306
{
crcBack = I2CRXD;
I2C_crcResUB = CRC8cal(TempBuf, 5);
I2C_SendAck(0);
//if(crcBack == I2C_crcResUB)
{
I2C_WriteDeviceBack(I2C_DeviceRegAddrUB , I2C_DeviceDtRtUW);// (u8 regAddr , u16 back)
}
// else
// {
// I2C_WriteDeviceBack(I2C_DeviceRegAddrUB , 0xffff);// (u8 regAddr , u16 back)
// }
I2C_StateFlowUW |= 0x2000;
}
// STEP 13
if(I2C_StateFlowUW == 0x4fff)// read CRC from SH367306
{
I2C_RecvData();
I2C_StateFlowUW |= 0x1000;
}
// STEP 12
if(I2C_StateFlowUW == 0x47ff)// read low byte of word register from SH367306
{
I2C_SendAck(0);
I2C_DeviceDtRtUW += I2CRXD;
TempBuf = I2CRXD;
I2C_StateFlowUW |= 0x800;
}
// STEP 11
if(I2C_StateFlowUW == 0x43ff)// read low byte of word register from SH367306
{
I2C_RecvData();
I2C_StateFlowUW |= 0x400;
}
// STEP 10
if(I2C_StateFlowUW == 0x41ff)// read high byte of word register from SH367306
{
I2C_DeviceDtRtUW = I2CRXD;
TempBuf = I2CRXD;
I2C_SendAck(0);
I2C_DeviceDtRtUW <<= 8;
I2C_StateFlowUW |= 0x200;
}
// STEP 9
if(I2C_StateFlowUW == 0x40ff)
{
I2C_RecvData();
I2C_StateFlowUW |= 0x100;
}
// STEP 8
if(I2C_StateFlowUW == 0x407f)// wait ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x80;
}
// STEP 7
if(I2C_StateFlowUW == 0x403f)// write SH367306 address for reading data
{
I2C_SendData(I2C_DeviceAdrrUB|0x01);
I2C_StateFlowUW |= 0x40;
}
// STEP 6
if(I2C_StateFlowUW == 0x401f)// RESTART SH367306 COMM -- very important
{
I2C_StartProc();
I2C_StateFlowUW |= 0x20;
}
// STEP 5
if(I2C_StateFlowUW == 0x400f)// RESTART SH367306 COMM -- very important
{
I2C_SendStop();
I2C_StateFlowUW |= 0x10;
}
// STEP 4
if(I2C_StateFlowUW == 0x4007)// wait ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x08;
}
// STEP 3
if(I2C_StateFlowUW == 0x4003)//
{
I2C_SendData(I2C_DeviceRegAddrUB);
I2C_StateFlowUW |= 0x04;
}
// STEP 2
if(I2C_StateFlowUW == 0x4001)// wait ack from SH367306
{
I2C_ReadAck();
I2C_StateFlowUW |= 0x02;
}
}
}
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