Motoo Tanaka
My trial of BME280 library, tested with Adafruit BME280 module
Diff: BME280.cpp
- Revision:
- 1:7b525853bad0
- Parent:
- 0:5ace1cc7a9f2
--- a/BME280.cpp Tue May 09 06:32:36 2017 +0000
+++ b/BME280.cpp Wed May 10 09:11:01 2017 +0000
@@ -54,7 +54,9 @@
#define REG_H2_LSB 0xE1
#define REG_H2_MSB 0xE2
#define REG_H3 0xE3
-
+#define REG_H4 0xE4
+#define REG_H5 0xE5
+#define REG_H6 0xE7
/*
* Register description
@@ -129,6 +131,28 @@
* 0xFD bit[7:0] hum_msb[7:0] MSB part uh[15:8]
* 0xFE bit[7:0] hum_lsb[7:0] LSB part uh[7:0]
*/
+ /*
+ * Compensation parameter storage, naming and data type
+ * Register addr, Register content, Data type
+ * 0x88/0x89, dig_T1[7:0]/[15:8], unsigned short
+ * 0x8A/0x8B, dig_T2[7:0]/[15:8], signed short
+ * 0x8C/0x8D, dig_T3[7:0]/[15:8], signed short
+ * 0x8E/0x8F, dig_P1[7:0]/[15:8], unsigned short
+ * 0x90/0x91, dig_P2[7:0]/[15:8], signed short
+ * 0x92/0x93, dig_P3[7:0]/[15:8], signed short
+ * 0x94/0x95, dig_P4[7:0]/[15:8], signed short
+ * 0x96/0x97, dig_P5[7:0]/[15:8], signed short
+ * 0x98/0x99, dig_P6[7:0]/[15:8], signed short
+ * 0x9A/0x9B, dig_P7[7:0]/[15:8], signed short
+ * 0x9C/0x9D, dig_P8[7:0]/[15:8], signed short
+ * 0x9E/0x9F, dig_P9[7:0]/[15:8], signed short
+ * 0xA1, dig_H1[7:0], unsigned char
+ * 0xE1/0xE2, dig_H2[7:0]/[15:8], signed short
+ * 0xE3, dig_H3[7:0], unsigned char
+ * 0xE4/0xE5[3:0], dig_H4[11:4]/[3:0] signed short
+ * 0xE5[7:4]/0xE6, dig_H5[3:0]/[11:4] signed short
+ * 0xE7, dig_H6[7:0], signed char
+ */
void BME280::init(void)
{
@@ -140,12 +164,10 @@
data[0] = REG_CTRL_MEAS ;
data[1] = (0x3 << 5) /* temp oversample x4 */
- | (0x3 << 3) /* pres oversample x4 */
+ | (0x3 << 2) /* pres oversample x4 */
| (0x00) /* Sleep Mode */
;
writeRegs(data, 2) ;
-readRegs(REG_CTRL_MEAS, data, 1) ;
-printf("ctrl_meas: 0x%02X\n", data[0]) ;
data[0] = REG_CONFIG ;
data[1] = (0x4 << 5) /* standby 500ms */
@@ -179,10 +201,19 @@
/* read dig_H regs */
readRegs(REG_H1, data, 1) ;
dig_H1 = data[0] ;
- readRegs(REG_H2_LSB, data, 3) ;
+ readRegs(REG_H2_LSB, data, 2) ;
dig_H2 = (data[1] << 8) | data[0] ;
- dig_H3 = data[2] ;
+ readRegs(REG_H3, data, 1) ;
+ dig_H3 = data[0] ;
+ readRegs(REG_H4, data, 3) ;
+ dig_H4 = (data[0] << 4) | (data[1] & 0x0F) ;
+ dig_H5 = (data[2] << 4) | (data[1] >> 4) ;
+ readRegs(REG_H6, data, 1) ;
+ dig_H6 = data[0] ;
// printf("dig_H1:0x%04X, dig_H2:0x%04X, dig_H3:0x%04X\n",dig_H1, dig_H2, dig_H3) ;
+// printf("dig_H4:0x%04X, dig_H5:0x%04X, dig_H6:0x%04X\n",dig_H4, dig_H5, dig_H6) ;
+
+ trigger() ; /* dummy measure */
}
BME280::BME280(PinName sda, PinName scl, int addr)
@@ -199,11 +230,6 @@
m_cs = new DigitalOut(cs, 1) ;
m_spi = new SPI(mosi, miso, sck) ;
m_spi->format(8, 3) ;
-#if 0
-#if defined (TARGET_KL25Z)
- *((uint8_t *)0x40076000) |= 0x01 ; /* lsb first */
-#endif
-#endif
m_i2c = 0 ;
m_addr = 0 ;
init() ;
@@ -235,7 +261,6 @@
*m_cs = 0 ;
m_spi->write(addr | 0x80) ;
for (int i = 0 ; i < len ; i++ ) {
- // m_spi->write((addr+i)|0x80) ; // spacify address to read
data[i] = m_spi->write((addr+i)|0x80) ;
}
m_spi->write(0x00) ; // to terminate read mode
@@ -245,7 +270,6 @@
void BME280::spi_writeRegs(uint8_t * data, int len) {
*m_cs = 0 ;
for (int i = 0 ; i < len-1 ; i++ ) {
-// printf("writing 0x%02X := 0x%02X\n", (data[0]+i)^0x80, data[i+1]) ;
m_spi->write((data[0]+i)^0x80) ; /* register address */
m_spi->write(data[i+1]) ; /* data to write */
@@ -288,7 +312,6 @@
data[1] = (data[1] & 0xFC) /* keep oversampling */
| (0x2) /* Forced Mode */
;
-// data[1] = 0x38 | 0x02 ;
writeRegs(data, 2) ;
}
@@ -306,98 +329,74 @@
return(data[0]) ;
}
-void BME280::readData(uint8_t data[])
-{
- readRegs(REG_PRESS_MSB, data, 8) ;
-printf("Data Read: ") ;
-for(int i = 0 ; i < 8 ; i++ ) {
- printf("%02X ", data[i]) ;
-}
-printf("\n") ;
-}
-
-float BME280::getTemperature(uint8_t data[])
+float BME280::getTemperature(void)
{
- uint32_t temp_raw;
- float tempf;
-// uint8_t data[3];
-
-// readRegs(REG_TEMP_MSB, data, 3) ;
-
- temp_raw = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4);
-
- int32_t temp;
-
- temp =
- (((((temp_raw >> 3) - (dig_T1 << 1))) * dig_T2) >> 11) +
- ((((((temp_raw >> 4) - dig_T1) * ((temp_raw >> 4) - dig_T1)) >> 12) * dig_T3) >> 14);
-
- t_fine = temp;
- temp = (temp * 5 + 128) >> 8;
- tempf = (float)temp;
-
+ float tempf ;
+ uint8_t data[3] ;
+ BME280_S32_t var1, var2, T ;
+ BME280_S32_t adc_T ;
+
+ readRegs(REG_TEMP_MSB, data, 3) ;
+ adc_T = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4);
+
+ var1 = ((((adc_T>>3) - ((BME280_S32_t)dig_T1<<1))) * ((BME280_S32_t)dig_T2)) >> 11;
+ var2 = (((((adc_T>>4) - ((BME280_S32_t)dig_T1)) * ((adc_T>>4) - ((BME280_S32_t)dig_T1))) >> 12) *
+ ((BME280_S32_t)dig_T3)) >> 14;
+ t_fine = var1 + var2;
+ T = (t_fine * 5 + 128) >> 8;
+
+ tempf = (float)T;
return (tempf/100.0f);
-
}
-float BME280::getHumidity(uint8_t data[])
+float BME280::getPressure(void)
{
- uint32_t hum_raw;
- float humf;
-// uint8_t data[2];
+ BME280_S32_t adc_P ;
+ BME280_S64_t var1, var2, p ;
+ float pressf;
+ uint8_t data[3];
-// readRegs(REG_HUM_MSB, data, 2) ;
-
- hum_raw = (data[0] << 8) | data[1];
-
- int32_t v_x1;
+ readRegs(REG_PRESS_MSB, data, 3) ;
+ adc_P = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4);
- v_x1 = t_fine - 76800;
- v_x1 = (((((hum_raw << 14) -(((int32_t)dig_H4) << 20) - (((int32_t)dig_H5) * v_x1)) +
- ((int32_t)16384)) >> 15) * (((((((v_x1 * (int32_t)dig_H6) >> 10) *
- (((v_x1 * ((int32_t)dig_H3)) >> 11) + 32768)) >> 10) + 2097152) *
- (int32_t)dig_H2 + 8192) >> 14));
- v_x1 = (v_x1 - (((((v_x1 >> 15) * (v_x1 >> 15)) >> 7) * (int32_t)dig_H1) >> 4));
- v_x1 = (v_x1 < 0 ? 0 : v_x1);
- v_x1 = (v_x1 > 419430400 ? 419430400 : v_x1);
+ var1 = ((BME280_S64_t)t_fine) - 128000;
+ var2 = var1 * var1 * (BME280_S64_t)dig_P6;
+ var2 = var2 + ((var1*(BME280_S64_t)dig_P5)<<17);
+ var2 = var2 + (((BME280_S64_t)dig_P4)<<35);
+ var1 = ((var1 * var1 * (BME280_S64_t)dig_P3)>>8) + ((var1 * (BME280_S64_t)dig_P2)<<12);
+ var1 = (((((BME280_S64_t)1)<<47)+var1))*((BME280_S64_t)dig_P1)>>33;
+ if (var1 == 0) {
+ return 0; // avoid exception caused by division by zero
+ }
+ p = 1048576-adc_P;
+ p = (((p<<31)-var2)*3125)/var1;
+ var1 = (((BME280_S64_t)dig_P9) * (p>>13) * (p>>13)) >> 25;
+ var2 = (((BME280_S64_t)dig_P8) * p) >> 19;
+ p = ((p + var1 + var2) >> 8) + (((BME280_S64_t)dig_P7)<<4);
- humf = (float)(v_x1 >> 12);
-
- return (humf/1024.0f);
+ pressf = (float)(p >> 8) ;
+ return (pressf/100.0f);
}
-float BME280::getPressure(uint8_t data[])
+float BME280::getHumidity(void)
{
- uint32_t press_raw;
- float pressf;
-// uint8_t data[3];
+ BME280_S32_t adc_H;
+ BME280_S32_t v_x1_u32r ;
+ float humf;
+ uint8_t data[2];
-// readRegs(REG_PRESS_MSB, data, 3) ;
-
- press_raw = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4);
-
- int32_t var1, var2;
- uint32_t press;
+ readRegs(REG_HUM_MSB, data, 2) ;
+ adc_H = (data[0] << 8) | data[1];
- var1 = (t_fine >> 1) - 64000;
- var2 = (((var1 >> 2) * (var1 >> 2)) >> 11) * dig_P6;
- var2 = var2 + ((var1 * dig_P5) << 1);
- var2 = (var2 >> 2) + (dig_P4 << 16);
- var1 = (((dig_P3 * (((var1 >> 2)*(var1 >> 2)) >> 13)) >> 3) + ((dig_P2 * var1) >> 1)) >> 18;
- var1 = ((32768 + var1) * dig_P1) >> 15;
- if (var1 == 0) {
- return 0;
- }
- press = (((1048576 - press_raw) - (var2 >> 12))) * 3125;
- if(press < 0x80000000) {
- press = (press << 1) / var1;
- } else {
- press = (press / var1) * 2;
- }
- var1 = ((int32_t)dig_P9 * ((int32_t)(((press >> 3) * (press >> 3)) >> 13))) >> 12;
- var2 = (((int32_t)(press >> 2)) * (int32_t)dig_P8) >> 13;
- press = (press + ((var1 + var2 + dig_P7) >> 4));
-
- pressf = (float)press;
- return (pressf/100.0f);
+ v_x1_u32r = (t_fine - ((BME280_S32_t)76800));
+ v_x1_u32r = (((((adc_H << 14) - (((BME280_S32_t)dig_H4) << 20) - (((BME280_S32_t)dig_H5) * v_x1_u32r)) +
+ ((BME280_S32_t)16384)) >> 15) * (((((((v_x1_u32r * ((BME280_S32_t)dig_H6)) >> 10) * (((v_x1_u32r *
+ ((BME280_S32_t)dig_H3)) >> 11) + ((BME280_S32_t)32768))) >> 10) + ((BME280_S32_t)2097152)) *
+ ((BME280_S32_t)dig_H2) + 8192) >> 14));
+ v_x1_u32r = (v_x1_u32r - (((((v_x1_u32r >> 15) * (v_x1_u32r >> 15)) >> 7) * ((BME280_S32_t)dig_H1)) >> 4));
+ v_x1_u32r = (v_x1_u32r < 0 ? 0 : v_x1_u32r);
+ v_x1_u32r = (v_x1_u32r > 419430400 ? 419430400 : v_x1_u32r);
+ humf = (float)(v_x1_u32r >> 12) ;
+
+ return (humf/1024.0f);
}
\ No newline at end of file