MLX90615驱动

#include "mlx90615.h" /********************************************************************** * Function Name : Mlx90614_Configuration * Description : Mlx90614_Configuration * Input : None * Output : None * Return : None **********************************************************************/ void Mlx96015_Configuration(void) { //GPIO_InitTypeDef GPIO_InitStructure; GPIO_InitTypeDef GPIO; //声明一个结构体变量 RCC_APB2PeriphClockCmd(RCC_AHBPeriph_GPIOC,ENABLE);//非接触温度传感器SDAL 连接 PB.12,SCL 连接 PB.13---打开 GPIOB 时钟 /*温度传感器引脚配置*/ GPIO.GPIO_Pin = (GPIO_Pin_11|GPIO_Pin_12);//非接触温度传感器 SDAL 连接 PB.12,SCL 连接 PB.13 GPIO.GPIO_Speed = GPIO_Speed_Level_3;//管脚频率为 50MHZ GPIO.GPIO_Mode =GPIO_Mode_OUT ;//输出模式 GPIO.GPIO_OType=GPIO_OType_OD; //为开漏 GPIO_Init(GPIOC,&GPIO);//初始化 GPIOB 寄存器 SDA_H; //拉高SDAL和SCL SCL_H; //因为 SMBus 是下降沿触发 } /********************************************************************** * Function Name : SMBus_StartBit * Description : Generate START condition on SMBus * Input : None * Output : None * Return : None **********************************************************************/ void SMBus_StartBit(void) { SDA_H; // Set SDA line SMBus_Delay(1); // Wait a few microseconds SCL_H; // Set SCK line SMBus_Delay(5); // Generate bus free time between Stop SDA_L; // Clear SDA line SMBus_Delay(10); // Hold time after (Repeated) Start // Condition. After this period, the first clock is generated. //(Thd:sta=4.0us min) SCL_L; // Clear SCK line SMBus_Delay(2); // Wait a few microseconds } /********************************************************************** * Function Name : SMBus_StopBit * Description : Generate STOP condition on SMBus * Input : None * Output : None * Return : None **********************************************************************/ void SMBus_StopBit(void) { SCL_L; // Clear SCK line SMBus_Delay(5); // Wait a few microseconds SDA_L; // Clear SDA line SMBus_Delay(5); // Wait a few microseconds SCL_H; // Set SCK line SMBus_Delay(10); // Stop condition setup time(Tsu:sto=4.0us min) SDA_H; // Set SDA line } /********************************************************************** * Function Name : SMBus_SendByte * Description : Send a byte on SMBus * Input : Tx_buffer * Output : None * Return : None **********************************************************************/ uint8_t SMBus_SendByte(uint8_t Tx_buffer) { uint8_t Bit_counter; uint8_t Ack_bit; uint8_t bit_out; for(Bit_counter=8; Bit_counter; Bit_counter--) { if (Tx_buffer&0x80) { bit_out=1; // If the current bit of Tx_buffer is 1 set bit_out } else { bit_out=0; // else clear bit_out } SMBus_SendBit(bit_out); // Send the current bit on SDA Tx_buffer<<=1; // Get next bit for checking } Ack_bit=SMBus_ReceiveBit(); // Get acknowledgment bit return Ack_bit; } /********************************************************************** * Function Name : SMBus_SendBit * Description : Send a bit on SMBus * Input : bit_out * Output : None * Return : None **********************************************************************/ void SMBus_SendBit(uint8_t bit_out) { if(bit_out==0) { SDA_L; } else { SDA_H; } SMBus_Delay(2); // Tsu:dat = 250ns minimum SCL_H; // Set SCK line SMBus_Delay(10); // High Level of Clock Pulse SCL_L; // Clear SCK line SMBus_Delay(10); // Low Level of Clock Pulse //SMBUS_SDA_H(); // Master release SDA line , return; } /********************************************************************** * Function Name : SMBus_ReceiveBit * Description : Receive a bit on SMBus * Input : None * Output : None * Return : Ack_bit **********************************************************************/ uint8_t SMBus_ReceiveBit(void) { uint8_t Ack_bit; SDA_H; //引脚靠外部电阻上拉， 当作输入 SCL_H; // Set SCL line SMBus_Delay(2); // High Level of Clock Pulse if (SMBUS_SDA_PIN) { Ack_bit=1; } else { Ack_bit=0; } SCL_L; // Clear SCL line SMBus_Delay(4); // Low Level of Clock Pulse return Ack_bit; } /********************************************************************** * Function Name : SMBus_ReceiveByte * Description : Receive a byte on SMBus * Input : ack_nack * Output : None * Return : RX_buffer **********************************************************************/ uint8_t SMBus_ReceiveByte(uint8_t ack_nack) { uint8_t RX_buffer; uint8_t Bit_Counter; for(Bit_Counter=8; Bit_Counter; Bit_Counter--) { if(SMBus_ReceiveBit()) // Get a bit from the SDA line { RX_buffer <<= 1; // If the bit is HIGH save 1 in RX_buffer RX_buffer |=0x01; } else { RX_buffer <<= 1; // If the bit is LOW save 0 in RX_buffer RX_buffer &=0xfe; } } SMBus_SendBit(ack_nack); // Sends acknowledgment bit return RX_buffer; } /********************************************************************** * Function Name : SMBus_Delay* Description : 延时 一次循环约 1us * Input : time * Output : None * Return : None **********************************************************************/ void SMBus_Delay(uint16_t time) { uint16_t i, j; for (i=0; i<4; i++) { for (j=0; j<time; j++); } } /************************************************************************** * Function Name : SMBus_ReadMemory * Description : READ DATA FROM RAM/EEPROM * Input : slaveAddress, command * Output : None * Return : Data ***************************************************************************/ uint16_t SMBus_ReadMemory(uint8_t slaveAddress, uint8_t command) { uint16_t data; // Data storage (DataH:DataL) uint8_t Pec; // PEC byte storage uint8_t DataL=0; // Low data byte storage uint8_t DataH=0; // High data byte storage uint8_t arr[6]; // Buffer for the sent bytes uint8_t PecReg; // Calculated PEC byte storage uint8_t ErrorCounter; // Defines the number of the attempts for communicationwith MLX90615 ErrorCounter=0x00; // Initialising of ErrorCounter slaveAddress <<= 1; //2-7 位表示从机地址 do { repeat: SMBus_StopBit(); //If slave send NACK stop comunication --ErrorCounter; //Pre-decrement ErrorCounter if(!ErrorCounter) //ErrorCounter=0? { break; //Yes,go out from do-while{} } SMBus_StartBit(); //Start condition if(SMBus_SendByte(slaveAddress))//Send SlaveAddress 最低位 Wr=0 表示接下来写命令 { goto repeat; //Repeat comunication again } if(SMBus_SendByte(command)) //Send command { goto repeat; //Repeat comunication again } SMBus_StartBit(); //Repeated Start condition if(SMBus_SendByte(slaveAddress+1)) //Send SlaveAddress 最低位 Rd=1 表示接下来读数据 { goto repeat; //Repeat comunication again } DataL = SMBus_ReceiveByte(ACK); //Read low data,master must send ACK DataH = SMBus_ReceiveByte(ACK); //Read high data,master must send ACK Pec = SMBus_ReceiveByte(NACK); //Read PEC byte, master must send NACK SMBus_StopBit(); //Stop condition arr[5] = slaveAddress; arr[4] = command; arr[3] = slaveAddress+1; //Load array arr arr[2] = DataL; arr[1] = DataH; arr[0] = 0; PecReg=PEC_Calculation(arr); //Calculate CRC } while(PecReg != Pec); //If received and calculated CRC are equal go out fromdo-while{} data = (DataH<<8) | DataL; //data=DataH:DataL return data; } /********************************************************************** * Function Name : PEC_calculatio