Mlx90640 infrared thermal imaging sensor temperature measurement module development notes (II)

MLX90640 Infrared thermal imager temperature measurement module development notes （ Two ）API transplant -I2C And key interface functions  

API There are official migration instructions in the documentation , But I think we can focus on MLX90640 Several functions related to specific operation , And with standards I2C The related functions and file structures are still implemented according to their customary routines . This is more in line with the controllable habits of our developers . Steps are as follows ：

（1） Establish standards I2C file IIC.h and IIC.c  

Use your own method to realize the following functions （ Hardware is good ,GPIO Simulation is good ）, The function name is suggested below .

void IIC_Init(void); //I2C Interface initialization

void IIC_Start(void); // Send the start signal

void IIC_Stop(void); // Send end signal

void IIC_SendACK(void); // Send reply signal

void IIC_SendNAK(void); // Send non reply signal unsigned char IIC_RecvACK(void); // Read the reply signal unsigned char IIC_RecvData(void); // Read 1 Bytes void IIC_SendData(char dat); // send out 1 Bytes

（2） Introduce... Into the project MLX90640_API.c  

And make the following modifications

first line #include <MLX90640_I2C_Driver.h> Change it to #include <IIC.h>

（3） add to 3 A function  

void MLX90640_I2CInit(void)

unsigned char MLX90640_I2CRead (unsigned short startAddress, unsigned short nWordsRead, unsigned short *datas)

unsigned char MLX90640_I2CWrite (unsigned short writeAddress, unsigned short word)

void MLX90640_I2CInit(void)

{

IIC_Stop();

}

// Read from the specified address n A word （ Occupied per word 2 Bytes ）

unsigned char MLX90640_I2CRead(unsigned short startAddress, unsigned short nWordsRead, unsigned short *datas)

{

unsigned char c1,c2; unsigned short i; unsigned char Msb,Lsb;

Msb=(unsigned char)(startAddress>>8); Lsb=(unsigned char)(startAddress&0x00FF);

IIC_Start(); // Send start command

IIC_SendData(0x66); // Send device address + Write orders IIC_RecvACK();

IIC_SendData(Msb); // Send the address value to be operated 2 byte

IIC_RecvACK();

IIC_SendData(Lsb);

IIC_RecvACK();

IIC_Start(); // Send start command

IIC_SendData(0x67); // Send device address + Read command IIC_RecvACK();

for (i=0;i<nWordsRead;i++)

{

c1=IIC_RecvData(); IIC_SendACK();

c2=IIC_RecvData();

if (i==(nWordsRead-1)) IIC_SendNAK();

else

IIC_SendACK();

datas[i]=c1; datas[i]<<=8; datas[i]|=c2;

}

IIC_Stop(); // Send stop command

return 0;

}

// Write... To the specified address 1 A word （2 byte ）

unsigned char MLX90640_I2CWrite(unsigned int writeAddress, unsigned int word)

{

IIC_Start(); // Send start command

IIC_SendData(0x66); // Send device address + Write orders IIC_RecvACK();

IIC_SendData(writeAddress>>8); // Send the address value to be operated 2 byte

IIC_RecvACK();

IIC_SendData(writeAddress&0x00FF); IIC_RecvACK();

IIC_SendData(word>>8); IIC_RecvACK();

IIC_SendData(word&0x00FF); IIC_RecvACK();

IIC_Stop(); return 0;

（4） modify 2 A function  

unsigned char MLX90640_DumpEE(unsigned short *eeData)

{

return MLX90640_I2CRead(0x2400, 832, eeData);

}

unsigned char MLX90640_GetFrameData(unsigned short *frameData)

{

unsigned short statusRegister,controlRegister1;

MLX90640_I2CRead(0x8000, 1, &statusRegister); if (statusRegister&0x0008)// There are measurements completed Frame

{

MLX90640_I2CRead(0x800D, 1, &controlRegister1); MLX90640_I2CWrite(0x8000, statusRegister&(~0x0018)); MLX90640_I2CRead(0x0400, 832, frameData); frameData[832] = controlRegister1;

frameData[833] = statusRegister & 0x0001; return 0;

}

Return -1;

}

So far, the migration is complete

Compiler Engineering , If there is no error prompt, there is basically no problem , The next chapter begins with how to operate MLX90640.