Teste de BME280 para Coragem
main.cpp
- Committer:
- brunnobbco
- Date:
- 2019-07-11
- Revision:
- 4:f772c1ae7c97
- Parent:
- 0:2c9585cecfde
File content as of revision 4:f772c1ae7c97:
#include "mbed.h" #define _DEBUG Serial pc(USBTX, USBRX); //I2C sensor(I2C_SDA, I2C_SCL); I2C sensor(p13, p15); #ifdef _DEBUG #define DEBUG_PRINT(...) pc.printf(__VA_ARGS__) #else #define DEBUG_PRINT(...) #endif const int BME280_ADDR = (0x77 << 1); uint16_t dig_T1; int16_t dig_T2, dig_T3; uint16_t dig_P1; int16_t dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9; uint16_t dig_H1, dig_H3; int16_t dig_H2, dig_H4, dig_H5, dig_H6; int32_t t_fine; void init() { char cmd[18]; sensor.frequency(1000000); cmd[0] = 0xf2; // ctrl_hum cmd[1] = 0x01; sensor.write(BME280_ADDR, cmd, 2); cmd[0] = 0xf4; // ctrl_meas cmd[1] = 0x27; sensor.write(BME280_ADDR, cmd, 2); cmd[0] = 0xf5; // config cmd[1] = 0xa0; sensor.write(BME280_ADDR, cmd, 2); cmd[0] = 0x88; // read dig_T regs sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, cmd, 6); dig_T1 = (cmd[1] << 8) | cmd[0]; dig_T2 = (cmd[3] << 8) | cmd[2]; dig_T3 = (cmd[5] << 8) | cmd[4]; DEBUG_PRINT("dig_T = 0x%x, 0x%x, 0x%x\n", dig_T1, dig_T2, dig_T3); cmd[0] = 0x8E; // read dig_P regs sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, cmd, 18); dig_P1 = (cmd[ 1] << 8) | cmd[ 0]; dig_P2 = (cmd[ 3] << 8) | cmd[ 2]; dig_P3 = (cmd[ 5] << 8) | cmd[ 4]; dig_P4 = (cmd[ 7] << 8) | cmd[ 6]; dig_P5 = (cmd[ 9] << 8) | cmd[ 8]; dig_P6 = (cmd[11] << 8) | cmd[10]; dig_P7 = (cmd[13] << 8) | cmd[12]; dig_P8 = (cmd[15] << 8) | cmd[14]; dig_P9 = (cmd[17] << 8) | cmd[16]; DEBUG_PRINT("dig_P = 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n", dig_P1, dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9); cmd[0] = 0xA1; // read dig_H regs sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, cmd, 9); dig_H1 = cmd[0]; dig_H2 = (cmd[2] << 8) | cmd[1]; dig_H3 = cmd[3]; dig_H4 = (cmd[4] << 4) | (cmd[5] & 0x0f); dig_H5 = (cmd[7] << 4) | ((cmd[6]>>4) & 0x0f); dig_H6 = cmd[8]; DEBUG_PRINT("dig_H = 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n", dig_H1, dig_H2, dig_H3, dig_H4, dig_H5, dig_H6); } float getTemperature() { uint32_t temp_raw; float tempf; char cmd[4]; cmd[0] = 0xfa; // temp_msb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[1], 1); cmd[0] = 0xfb; // temp_lsb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[2], 1); cmd[0] = 0xfc; // temp_xlsb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[3], 1); temp_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 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; return (tempf/100.0f); } float getPressure() { uint32_t press_raw; float pressf; char cmd[4]; cmd[0] = 0xf7; // press_msb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[1], 1); cmd[0] = 0xf8; // press_lsb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[2], 1); cmd[0] = 0xf9; // press_xlsb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[3], 1); press_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4); int32_t var1, var2; uint32_t press; 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); } float getHumidity() { uint32_t hum_raw; float humf; char cmd[4]; cmd[0] = 0xfd; // hum_msb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[1], 1); cmd[0] = 0xfd; // hum_lsb sensor.write(BME280_ADDR, cmd, 1); sensor.read(BME280_ADDR, &cmd[2], 1); hum_raw = (cmd[1] << 8) | cmd[2]; int32_t v_x1; 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); humf = (float)(v_x1 >> 12); return (humf/1024.0f); } int main() { pc.printf("\nBME280 test program\n"); init(); while(1) { pc.printf("%2.2f degC, %04.2f hPa, %2.2f %%\n", getTemperature(), getPressure(), getHumidity()); wait(1); } }