common/I2C/BMP280.c

   1 #define F_CPU 8000000UL\r
   2 #include <avr/io.h>\r
   3 #include <avr/interrupt.h>\r
   4 #include <util/delay.h>\r
   5 #include <avr/wdt.h>\r
   6 #include <avr/sleep.h>\r
   7 #include "USI_TWI_Master.h"\r
   8 \r
   9 uint16_t dig_T1;\r
  10 int16_t dig_T2;\r
  11 int16_t dig_T3;\r
  12 uint16_t dig_P1;\r
  13 int16_t dig_P2;\r
  14 int16_t dig_P3;\r
  15 int16_t dig_P4;\r
  16 int16_t dig_P5;\r
  17 int16_t dig_P6;\r
  18 int16_t dig_P7;\r
  19 int16_t dig_P8;\r
  20 int16_t dig_P9;\r
  21 \r
  22 \r
  23 \r
  24 \r
  25 short bmp280ReadShort(unsigned char address)\r
  26 {\r
  27         char msb, lsb;\r
  28         short data;\r
  29         I2c_StartCondition();\r
  30         I2c_WriteByte(0xEC);\r
  31         I2c_WriteByte(address);\r
  32         I2c_StopCondition();\r
  33         I2c_StartCondition();\r
  34         I2c_WriteByte(0xED);\r
  35         lsb=I2c_ReadByte(ACK);\r
  36         msb=I2c_ReadByte(NO_ACK);\r
  37         I2c_StopCondition();\r
  38         \r
  39 \r
  40         \r
  41         data = msb << 8;\r
  42         data |= lsb;\r
  43         \r
  44         return data;\r
  45 }\r
  46 \r
  47 void bmp280Init(void) {\r
  48         dig_T1=bmp280ReadShort(0x88);\r
  49         dig_T2=bmp280ReadShort(0x8A);\r
  50         dig_T3=bmp280ReadShort(0x8C);\r
  51         dig_P1=bmp280ReadShort(0x8E);\r
  52         dig_P2=bmp280ReadShort(0x90);\r
  53         dig_P3=bmp280ReadShort(0x92);\r
  54         dig_P4=bmp280ReadShort(0x94);\r
  55         dig_P5=bmp280ReadShort(0x96);\r
  56         dig_P6=bmp280ReadShort(0x98);\r
  57         dig_P7=bmp280ReadShort(0x9A);\r
  58         dig_P8=bmp280ReadShort(0x9C);\r
  59         dig_P9=bmp280ReadShort(0x9E);\r
  60         I2c_StartCondition();\r
  61         I2c_WriteByte(0xEC);\r
  62         I2c_WriteByte(0xF4);\r
  63         I2c_WriteByte(0b01010111); //2x Temp over 16x Press over   Normal mode\r
  64         I2c_WriteByte(0b11100000);  //4s time / no IIfilter\r
  65         I2c_StopCondition();\r
  66         \r
  67         \r
  68 }\r
  69 int32_t bmp280ReadTemp(void) {\r
  70         uint8_t msb, lsb,xlsb;\r
  71         volatile int32_t data;\r
  72         I2c_StartCondition();\r
  73         I2c_WriteByte(0xEC);\r
  74         I2c_WriteByte(0xFA);\r
  75         I2c_StopCondition();\r
  76         I2c_StartCondition();\r
  77         I2c_WriteByte(0xED);\r
  78         msb=I2c_ReadByte(ACK);\r
  79         lsb=I2c_ReadByte(ACK);\r
  80         xlsb=I2c_ReadByte(NO_ACK);\r
  81         I2c_StopCondition();\r
  82                 \r
  83         data = (int32_t)msb << 12;\r
  84         data |= (int16_t)lsb<<4;\r
  85         data|=xlsb>>4;\r
  86                 \r
  87                 return data;\r
  88 \r
  89         \r
  90 }\r
  91 int32_t bmp280ReadPressure(uint8_t oss) {\r
  92                 uint8_t msb, lsb,xlsb;\r
  93                 volatile int32_t data;\r
  94                 I2c_StartCondition();\r
  95                 I2c_WriteByte(0xEC);\r
  96                 I2c_WriteByte(0xF7);\r
  97                 I2c_StopCondition();\r
  98                 I2c_StartCondition();\r
  99                 I2c_WriteByte(0xED);\r
 100                 msb=I2c_ReadByte(ACK);\r
 101                 lsb=I2c_ReadByte(ACK);\r
 102                 xlsb=I2c_ReadByte(NO_ACK);\r
 103                 I2c_StopCondition();\r
 104                 \r
 105                 data = (int32_t)msb << 12;\r
 106                 data |= (int16_t)lsb<<4;\r
 107                 data|=xlsb>>4;\r
 108                 \r
 109                 return data;\r
 110 \r
 111 \r
 112 }\r
 113 void bmp280ConvertInt(int32_t * temperature,uint32_t *pressure,uint8_t oss) {\r
 114         int32_t var1,var2,T,t_fine;\r
 115         \r
 116         \r
 117         int32_t adc_T=bmp280ReadTemp();\r
 118         var1 = ((((adc_T>>3) - ((int32_t)dig_T1<<1))) * ((int32_t)dig_T2)) >> 11;\r
 119         var2 = ((((((adc_T>>4) - ((int32_t)dig_T1)) * ((adc_T>>4) - (int32_t)dig_T1))) >> 12) *((int32_t)dig_T3)) >> 14;\r
 120         t_fine = var1 + var2;\r
 121         T = (t_fine * 5 + 128) >> 8;\r
 122         *temperature=T;\r
 123         int32_t adc_P= bmp280ReadPressure(oss);\r
 124         uint32_t p;\r
 125         var1 = (((int32_t)t_fine)>>1) - (int32_t)64000;\r
 126         var2 = (((var1>>2) * (var1>>2)) >> 11 ) * ((int32_t)dig_P6);\r
 127         var2 = var2 + ((var1*((int32_t)dig_P5))<<1);\r
 128         var2 = (var2>>2)+(((int32_t)dig_P4)<<16);\r
 129         var1 = (((dig_P3 * (((var1>>2) * (var1>>2)) >> 13 )) >> 3) + ((((int32_t)dig_P2) * var1)>>1))>>18;\r
 130         var1 =((((32768+var1))*((int32_t)dig_P1))>>15);\r
 131         if (var1 == 0) {\r
 132                 return ; // avoid exception caused by division by zero\r
 133         }\r
 134         p = (((uint32_t)(((int32_t)1048576)-adc_P)-(var2>>12)))*3125;\r
 135         if (p < 0x80000000){\r
 136                 p = (p << 1) / ((uint32_t)var1);\r
 137                 }else{\r
 138                 p = (p / (uint32_t)var1) * 2;\r
 139         }\r
 140         var1 = (((int32_t)dig_P9) * ((int32_t)(((p>>3) * (p>>3))>>13)))>>12;\r
 141         var2 = (((int32_t)(p>>2)) * ((int32_t)dig_P8))>>13;\r
 142         p = (uint32_t)((int32_t)p + ((var1 + var2 + dig_P7) >> 4));\r
 143         *pressure=p;\r
 144 \r
 145 }\r
 146 void bmp280Convert(double * temperature, double * pressure,uint8_t oss) {\r
 147 \r
 148         uint32_t p;\r
 149         int32_t T;\r
 150         bmp280ConvertInt(&T,&p,oss);\r
 151         *temperature=T/100.0;\r
 152         *pressure=p/100.0;\r
 153 }\r
 154                 \r
 155                 \r
 156                 \r
 157 \r
 158         \r