BME280.hpp

00001 #include "mbed.h"
00002 #define size 14
00003 Serial sensor(PA_11,PA_12);
00004 Serial pc(USBTX,USBRX);
00005 int AT[3] = {0xA5,0x52,0xF7};
00006 class BME280{
00007 public:
00008     void judgement_data(char buf[]);
00009     int Temp_read();
00010 
00011 private:
00012     void receive();
00013     void send_AT();
00014     char buf[size];
00015     int Lux,Temp,Preesure,Hum,Height;
00016 
00017 };
00018 void BME280::judgement_data(char buf[]){
00019     int i=0;
00020     if(buf[i++]== 0x5A){
00021         //pc.printf("first_step\n");
00022         if(buf[i++]== 0x5A){
00023             //pc.printf("second_step\n");
00024            //i++;//go to data type
00025             if(buf[i] == 0x15){
00026                 //pc.printf("Lux type\n");
00027                 i++;//04
00028                 Lux = ((buf[i+1]<<24) | (buf[i+2]<<16) | (buf[i+3]<<8) | buf[i+4])/100;
00029                 //Lux = (0x00<<24) | (0x00<<16) | (0xFE<<8) | 0x40;//test
00030                 //pc.printf("Lux = %d\n", Lux);
00031             }else if(buf[i] == 0x45){
00032                 //pc.printf("temp type\n");
00033                 i++;//0A
00034                 Temp = ((buf[i+1]<<8)|(buf[i+2]))/100;
00035                 Preesure = ((buf[i+3]<<24)|(buf[i+4]<<16)|(buf[i+5]<<8)|(buf[i+6]))/100;
00036                 Hum = ((buf[i+7]<<8)|(buf[i+8]))/100;
00037                 Height = ((buf[i+9]<<8)|(buf[i+10]));
00038                 //pc.printf("Temp = %d\n", Temp);
00039                 //pc.printf("Preesure = %d\n", Preesure);
00040                 //pc.printf("Hum = %d\n", Hum);
00041                 //pc.printf("Height = %d\n", Height);
00042             }
00043         }
00044     }
00045 }
00046 void BME280::receive(){
00047     for(int i=0;i<size;i++){
00048         buf[i] = sensor.getc();  
00049         //pc.putc(buf[i]);
00050     }
00051     
00052 }
00053 void BME280::send_AT(){
00054     for(int i=0;i<3;i++){
00055         sensor.putc(AT[i]);
00056         //pc.putc(AT[i]);
00057     }
00058 }
00059 int BME280::Temp_read(){
00060     send_AT();
00061     //wait(0.2);
00062     receive();
00063     //wait(0.2);
00064     judgement_data(this->buf);
00065     
00066     return Temp;
00067 }