Merge pull request #165 from ourairquality/bmp180-rework
bmp180: make a lower level interface available and support oversampling.
This commit is contained in:
sheinz
GitHub
commit
964a2f850a
3 changed files with 230 additions and 194 deletions
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@ -73,7 +73,7 @@ void bmp180_task(void *pvParameters)
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bmp180_trigger_measurement(com_queue);
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bmp180_trigger_measurement(com_queue);
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break;
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break;
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case MY_EVT_BMP180:
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case MY_EVT_BMP180:
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printf("%s: Received BMP180 Event temp:=%d.%d°C press=%d.%02dhPa\n", __FUNCTION__, \
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printf("%s: Received BMP180 Event temp:=%d.%dC press=%d.%02dhPa\n", __FUNCTION__, \
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(int32_t)ev.bmp180_data.temperature, abs((int32_t)(ev.bmp180_data.temperature*10)%10), \
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(int32_t)ev.bmp180_data.temperature, abs((int32_t)(ev.bmp180_data.temperature*10)%10), \
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ev.bmp180_data.pressure/100, ev.bmp180_data.pressure%100 );
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ev.bmp180_data.pressure/100, ev.bmp180_data.pressure%100 );
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break;
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break;
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@ -27,12 +27,7 @@
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// Values for BMP180_CONTROL_REG
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// Values for BMP180_CONTROL_REG
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//
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//
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#define BMP180_MEASURE_TEMP 0x2E
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#define BMP180_MEASURE_TEMP 0x2E
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#define BMP180_MEASURE_PRESS_OSS0 0x34
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#define BMP180_MEASURE_PRESS 0x34
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#define BMP180_MEASURE_PRESS_OSS1 0x74
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#define BMP180_MEASURE_PRESS_OSS2 0xB4
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#define BMP180_MEASURE_PRESS_OSS3 0xF4
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#define BMP180_DEFAULT_CONV_TIME 5000
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//
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//
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// CHIP ID stored in BMP180_VERSION_REG
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// CHIP ID stored in BMP180_VERSION_REG
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@ -44,6 +39,176 @@
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//
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//
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#define BMP180_RESET_VALUE 0xB6
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#define BMP180_RESET_VALUE 0xB6
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static bool bmp180_readRegister16(uint8_t reg, int16_t *r)
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{
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uint8_t d[] = { 0, 0 };
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if (!i2c_slave_read(BMP180_DEVICE_ADDRESS, reg, d, 2))
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return false;
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*r = ((int16_t)d[0] << 8) | (d[1]);
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return true;
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}
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static bool bmp180_start_Messurement(uint8_t cmd)
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{
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uint8_t d[] = { BMP180_CONTROL_REG, cmd };
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return i2c_slave_write(BMP180_DEVICE_ADDRESS, d, 2);
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}
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static bool bmp180_get_uncompensated_temperature(int32_t *ut)
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{
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// Write Start Code into reg 0xF4.
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if (!bmp180_start_Messurement(BMP180_MEASURE_TEMP))
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return false;
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// Wait 5ms, datasheet states 4.5ms
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sdk_os_delay_us(5000);
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int16_t v;
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if (!bmp180_readRegister16(BMP180_OUT_MSB_REG, &v))
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return false;
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*ut = v;
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return true;
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}
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static bool bmp180_get_uncompensated_pressure(uint8_t oss, uint32_t *up)
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{
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uint16_t us;
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// Limit oss and set the measurement wait time. The datasheet
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// states 4.5, 7.5, 13.5, 25.5ms for oss 0 to 3.
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switch (oss) {
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case 0: us = 5000; break;
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case 1: us = 8000; break;
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case 2: us = 14000; break;
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default: oss = 3; us = 26000; break;
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}
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// Write Start Code into reg 0xF4
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if (!bmp180_start_Messurement(BMP180_MEASURE_PRESS | (oss << 6)))
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return false;
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sdk_os_delay_us(us);
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uint8_t d[] = { 0, 0, 0 };
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if (!i2c_slave_read(BMP180_DEVICE_ADDRESS, BMP180_OUT_MSB_REG, d, 3))
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return false;
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uint32_t r = ((uint32_t)d[0] << 16) | ((uint32_t)d[1] << 8) | d[2];
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r >>= 8 - oss;
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*up = r;
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return true;
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}
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// Returns true of success else false.
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bool bmp180_fillInternalConstants(bmp180_constants_t *c)
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{
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if (!bmp180_readRegister16(BMP180_CALIBRATION_REG+0, &c->AC1) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+2, &c->AC2) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+4, &c->AC3) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+6, (int16_t *)&c->AC4) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+8, (int16_t *)&c->AC5) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+10, (int16_t *)&c->AC6) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+12, &c->B1) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+14, &c->B2) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+16, &c->MB) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+18, &c->MC) ||
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!bmp180_readRegister16(BMP180_CALIBRATION_REG+20, &c->MD)) {
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return false;
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}
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#ifdef BMP180_DEBUG
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printf("%s: AC1:=%d AC2:=%d AC3:=%d AC4:=%u AC5:=%u AC6:=%u \n", __FUNCTION__, c->AC1, c->AC2, c->AC3, c->AC4, c->AC5, c->AC6);
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printf("%s: B1:=%d B2:=%d\n", __FUNCTION__, c->B1, c->B2);
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printf("%s: MB:=%d MC:=%d MD:=%d\n", __FUNCTION__, c->MB, c->MC, c->MD);
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#endif
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// Error if any read as 0x0000 or 0xffff.
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return !(c->AC1 == 0x0000 || c->AC2 == 0x0000 || c->AC3 == 0x0000 ||
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c->AC4 == 0x0000 || c->AC5 == 0x0000 || c->AC6 == 0x0000 ||
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c->B1 == 0x0000 || c->B2 == 0x0000 ||
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c->MB == 0x0000 || c->MC == 0x0000 || c->MD == 0x0000 ||
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c->AC1 == 0xffff || c->AC2 == 0xffff || c->AC3 == 0xffff ||
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c->AC4 == 0xffff || c->AC5 == 0xffff || c->AC6 == 0xffff ||
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c->B1 == 0xffff || c->B2 == 0xffff ||
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c->MB == 0xffff || c->MC == 0xffff || c->MD == 0xffff);
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}
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bool bmp180_is_available()
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{
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uint8_t id;
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return i2c_slave_read(BMP180_DEVICE_ADDRESS, BMP180_VERSION_REG, &id, 1) &&
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id == BMP180_CHIP_ID;
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}
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bool bmp180_measure(bmp180_constants_t *c, int32_t *temperature,
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uint32_t *pressure, uint8_t oss)
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{
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int32_t T, P;
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if (!temperature && !pressure)
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return false;
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// Temperature is always needed, allso required for pressure only.
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//
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// Calculation taken from BMP180 Datasheet
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int32_t UT, X1, X2, B5;
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if (!bmp180_get_uncompensated_temperature(&UT))
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return false;
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X1 = ((UT - (int32_t)c->AC6) * (int32_t)c->AC5) >> 15;
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X2 = ((int32_t)c->MC << 11) / (X1 + (int32_t)c->MD);
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B5 = X1 + X2;
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T = (B5 + 8) >> 4;
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if (temperature)
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*temperature = T;
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#ifdef BMP180_DEBUG
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printf("%s: T:= %ld.%d\n", __FUNCTION__, T/10, abs(T%10));
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#endif
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if (pressure) {
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int32_t X3, B3, B6;
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uint32_t B4, B7, UP;
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if (!bmp180_get_uncompensated_pressure(oss, &UP))
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return false;
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// Calculation taken from BMP180 Datasheet
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B6 = B5 - 4000;
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X1 = ((int32_t)c->B2 * ((B6 * B6) >> 12)) >> 11;
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X2 = ((int32_t)c->AC2 * B6) >> 11;
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X3 = X1 + X2;
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B3 = ((((int32_t)c->AC1 * 4 + X3) << oss) + 2) >> 2;
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X1 = ((int32_t)c->AC3 * B6) >> 13;
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X2 = ((int32_t)c->B1 * ((B6 * B6) >> 12)) >> 16;
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X3 = ((X1 + X2) + 2) >> 2;
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B4 = ((uint32_t)c->AC4 * (uint32_t)(X3 + 32768)) >> 15;
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B7 = ((uint32_t)UP - B3) * (uint32_t)(50000UL >> oss);
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if (B7 < 0x80000000UL) {
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P = (B7 * 2) / B4;
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} else {
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P = (B7 / B4) * 2;
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}
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X1 = (P >> 8) * (P >> 8);
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X1 = (X1 * 3038) >> 16;
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X2 = (-7357 * P) >> 16;
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P = P + ((X1 + X2 + (int32_t)3791) >> 4);
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if (pressure)
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*pressure = P;
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#ifdef BMP180_DEBUG
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printf("%s: P:= %ld\n", __FUNCTION__, P);
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#endif
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}
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return true;
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}
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// BMP180_Event_Command
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// BMP180_Event_Command
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typedef struct
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typedef struct
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@ -56,25 +221,9 @@ typedef struct
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static xQueueHandle bmp180_rx_queue = NULL;
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static xQueueHandle bmp180_rx_queue = NULL;
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static xTaskHandle bmp180_task_handle = NULL;
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static xTaskHandle bmp180_task_handle = NULL;
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// Calibration constants
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static int16_t AC1;
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static int16_t AC2;
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static int16_t AC3;
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static uint16_t AC4;
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static uint16_t AC5;
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static uint16_t AC6;
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static int16_t B1;
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static int16_t B2;
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static int16_t MB;
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static int16_t MC;
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static int16_t MD;
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//
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//
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// Forward declarations
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// Forward declarations
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//
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//
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static void bmp180_meassure(const bmp180_command_t* command);
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static bool bmp180_informUser_Impl(const xQueueHandle* resultQueue, uint8_t cmd, bmp180_temp_t temperature, bmp180_press_t pressure);
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static bool bmp180_informUser_Impl(const xQueueHandle* resultQueue, uint8_t cmd, bmp180_temp_t temperature, bmp180_press_t pressure);
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// Set default implementation .. User gets result as bmp180_result_t event
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// Set default implementation .. User gets result as bmp180_result_t event
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@ -85,109 +234,53 @@ static void bmp180_driver_task(void *pvParameters)
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{
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{
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// Data to be received from user
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// Data to be received from user
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bmp180_command_t current_command;
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bmp180_command_t current_command;
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bmp180_constants_t bmp180_constants;
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#ifdef BMP180_DEBUG
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#ifdef BMP180_DEBUG
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// Wait for commands from the outside
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// Wait for commands from the outside
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printf("%s: Started Task\n", __FUNCTION__);
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printf("%s: Started Task\n", __FUNCTION__);
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#endif
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#endif
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while(1)
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// Initialize all internal constants.
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{
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if (!bmp180_fillInternalConstants(&bmp180_constants)) {
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printf("%s: reading internal constants failed\n", __FUNCTION__);
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vTaskDelete(NULL);
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}
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while(1) {
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// Wait for user to insert commands
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// Wait for user to insert commands
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if (xQueueReceive(bmp180_rx_queue, ¤t_command, portMAX_DELAY) == pdTRUE)
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if (xQueueReceive(bmp180_rx_queue, ¤t_command, portMAX_DELAY) == pdTRUE) {
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{
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#ifdef BMP180_DEBUG
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#ifdef BMP180_DEBUG
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printf("%s: Received user command %d 0x%p\n", __FUNCTION__, current_command.cmd, current_command.resultQueue);
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printf("%s: Received user command %d 0x%p\n", __FUNCTION__, current_command.cmd, current_command.resultQueue);
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#endif
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#endif
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// use user provided queue
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// use user provided queue
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if (current_command.resultQueue != NULL)
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if (current_command.resultQueue != NULL) {
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{
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// Work on it ...
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// Work on it ...
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bmp180_meassure(¤t_command);
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int32_t T = 0;
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uint32_t P = 0;
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if (bmp180_measure(&bmp180_constants, &T, (current_command.cmd & BMP180_PRESSURE) ? &P : NULL, 3)) {
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// Inform the user ...
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if (!bmp180_informUser(current_command.resultQueue,
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current_command.cmd,
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((bmp180_temp_t)T)/10.0,
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(bmp180_press_t)P)) {
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// Failed to send info to user
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printf("%s: Unable to inform user bmp180_informUser returned \"false\"\n", __FUNCTION__);
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}
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}
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}
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}
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}
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}
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}
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static uint8_t bmp180_readRegister8(uint8_t reg)
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{
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uint8_t r = 0;
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if (!i2c_slave_read(BMP180_DEVICE_ADDRESS, reg, &r, 1))
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{
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r = 0;
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}
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}
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return r;
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}
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static int16_t bmp180_readRegister16(uint8_t reg)
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{
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uint8_t d[] = { 0, 0 };
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int16_t r = 0;
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if (i2c_slave_read(BMP180_DEVICE_ADDRESS, reg, d, 2))
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{
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r = ((int16_t)d[0]<<8) | (d[1]);
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}
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}
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return r;
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}
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static void bmp180_start_Messurement(uint8_t cmd)
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{
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uint8_t d[] = { BMP180_CONTROL_REG, cmd };
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i2c_slave_write(BMP180_DEVICE_ADDRESS, d, 2);
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}
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static int16_t bmp180_getUncompensatedMessurement(uint8_t cmd)
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{
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// Write Start Code into reg 0xF4 (Currently without oversampling ...)
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bmp180_start_Messurement((cmd==BMP180_TEMPERATURE)?BMP180_MEASURE_TEMP:BMP180_MEASURE_PRESS_OSS0);
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// Wait 5ms Datasheet states 4.5ms
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sdk_os_delay_us(BMP180_DEFAULT_CONV_TIME);
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return (int16_t)bmp180_readRegister16(BMP180_OUT_MSB_REG);
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}
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static void bmp180_fillInternalConstants(void)
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{
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AC1 = bmp180_readRegister16(BMP180_CALIBRATION_REG+0);
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AC2 = bmp180_readRegister16(BMP180_CALIBRATION_REG+2);
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AC3 = bmp180_readRegister16(BMP180_CALIBRATION_REG+4);
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AC4 = bmp180_readRegister16(BMP180_CALIBRATION_REG+6);
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AC5 = bmp180_readRegister16(BMP180_CALIBRATION_REG+8);
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AC6 = bmp180_readRegister16(BMP180_CALIBRATION_REG+10);
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B1 = bmp180_readRegister16(BMP180_CALIBRATION_REG+12);
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B2 = bmp180_readRegister16(BMP180_CALIBRATION_REG+14);
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MB = bmp180_readRegister16(BMP180_CALIBRATION_REG+16);
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MC = bmp180_readRegister16(BMP180_CALIBRATION_REG+18);
|
|
||||||
MD = bmp180_readRegister16(BMP180_CALIBRATION_REG+20);
|
|
||||||
|
|
||||||
#ifdef BMP180_DEBUG
|
|
||||||
printf("%s: AC1:=%d AC2:=%d AC3:=%d AC4:=%u AC5:=%u AC6:=%u \n", __FUNCTION__, AC1, AC2, AC3, AC4, AC5, AC6);
|
|
||||||
printf("%s: B1:=%d B2:=%d\n", __FUNCTION__, B1, B2);
|
|
||||||
printf("%s: MB:=%d MC:=%d MD:=%d\n", __FUNCTION__, MB, MC, MD);
|
|
||||||
#endif
|
|
||||||
}
|
}
|
||||||
|
|
||||||
static bool bmp180_create_communication_queues()
|
static bool bmp180_create_communication_queues()
|
||||||
{
|
{
|
||||||
// Just create them once
|
// Just create them once
|
||||||
if (bmp180_rx_queue==NULL)
|
if (bmp180_rx_queue == NULL)
|
||||||
{
|
|
||||||
bmp180_rx_queue = xQueueCreate(BMP180_RX_QUEUE_SIZE, sizeof(bmp180_result_t));
|
bmp180_rx_queue = xQueueCreate(BMP180_RX_QUEUE_SIZE, sizeof(bmp180_result_t));
|
||||||
}
|
|
||||||
|
|
||||||
return (bmp180_rx_queue!=NULL);
|
return bmp180_rx_queue != NULL;
|
||||||
}
|
|
||||||
|
|
||||||
static bool bmp180_is_avaialble()
|
|
||||||
{
|
|
||||||
return (bmp180_readRegister8(BMP180_VERSION_REG)==BMP180_CHIP_ID);
|
|
||||||
}
|
}
|
||||||
|
|
||||||
static bool bmp180_createTask()
|
static bool bmp180_createTask()
|
||||||
|
|
@ -195,87 +288,10 @@ static bool bmp180_createTask()
|
||||||
// We already have a task
|
// We already have a task
|
||||||
portBASE_TYPE x = pdPASS;
|
portBASE_TYPE x = pdPASS;
|
||||||
|
|
||||||
if (bmp180_task_handle==NULL)
|
if (bmp180_task_handle == NULL) {
|
||||||
{
|
|
||||||
x = xTaskCreate(bmp180_driver_task, (signed char *)"bmp180_driver_task", 256, NULL, BMP180_TASK_PRIORITY, &bmp180_task_handle);
|
x = xTaskCreate(bmp180_driver_task, (signed char *)"bmp180_driver_task", 256, NULL, BMP180_TASK_PRIORITY, &bmp180_task_handle);
|
||||||
}
|
}
|
||||||
return (x==pdPASS);
|
return x == pdPASS;
|
||||||
}
|
|
||||||
|
|
||||||
static void bmp180_meassure(const bmp180_command_t* command)
|
|
||||||
{
|
|
||||||
int32_t T, P;
|
|
||||||
|
|
||||||
// Init result to 0
|
|
||||||
T = P = 0;
|
|
||||||
|
|
||||||
if (command->resultQueue != NULL)
|
|
||||||
{
|
|
||||||
int32_t UT, X1, X2, B5;
|
|
||||||
|
|
||||||
//
|
|
||||||
// Temperature is always needed ... Also required for pressure only
|
|
||||||
//
|
|
||||||
// Calculation taken from BMP180 Datasheet
|
|
||||||
UT = (int32_t)bmp180_getUncompensatedMessurement(BMP180_TEMPERATURE);
|
|
||||||
|
|
||||||
X1 = (UT - (int32_t)AC6) * ((int32_t)AC5) >> 15;
|
|
||||||
X2 = ((int32_t)MC << 11) / (X1 + (int32_t)MD);
|
|
||||||
B5 = X1 + X2;
|
|
||||||
|
|
||||||
T = (B5 + 8) >> 4;
|
|
||||||
|
|
||||||
#ifdef BMP180_DEBUG
|
|
||||||
printf("%s: T:= %ld.%d\n", __FUNCTION__, T/10, abs(T%10));
|
|
||||||
#endif
|
|
||||||
|
|
||||||
// Do we also need pressure?
|
|
||||||
if (command->cmd & BMP180_PRESSURE)
|
|
||||||
{
|
|
||||||
int32_t X3, B3, B6;
|
|
||||||
uint32_t B4, B7, UP;
|
|
||||||
|
|
||||||
UP = ((uint32_t)bmp180_getUncompensatedMessurement(BMP180_PRESSURE) & 0xFFFF);
|
|
||||||
|
|
||||||
// Calculation taken from BMP180 Datasheet
|
|
||||||
B6 = B5 - 4000;
|
|
||||||
X1 = ((int32_t)B2 * ((B6 * B6) >> 12)) >> 11;
|
|
||||||
X2 = ((int32_t)AC2 * B6) >> 11;
|
|
||||||
X3 = X1 + X2;
|
|
||||||
|
|
||||||
B3 = (((int32_t)AC1 * 4 + X3) + 2) >> 2;
|
|
||||||
X1 = ((int32_t)AC3 * B6) >> 13;
|
|
||||||
X2 = ((int32_t)B1 * ((B6 * B6) >> 12)) >> 16;
|
|
||||||
X3 = ((X1 + X2) + 2) >> 2;
|
|
||||||
B4 = ((uint32_t)AC4 * (uint32_t)(X3 + 32768)) >> 15;
|
|
||||||
B7 = (UP - B3) * (uint32_t)(50000UL);
|
|
||||||
|
|
||||||
if (B7 < 0x80000000)
|
|
||||||
{
|
|
||||||
P = (B7 * 2) / B4;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
P = (B7 / B4) * 2;
|
|
||||||
}
|
|
||||||
|
|
||||||
X1 = (P >> 8) * (P >> 8);
|
|
||||||
X1 = (X1 * 3038) >> 16;
|
|
||||||
X2 = (-7357 * P) >> 16;
|
|
||||||
P = P + ((X1 + X2 + (int32_t)3791) >> 4);
|
|
||||||
|
|
||||||
#ifdef BMP180_DEBUG
|
|
||||||
printf("%s: P:= %ld\n", __FUNCTION__, P);
|
|
||||||
#endif
|
|
||||||
}
|
|
||||||
|
|
||||||
// Inform the user ...
|
|
||||||
if (!bmp180_informUser(command->resultQueue, command->cmd, ((bmp180_temp_t)T)/10.0, (bmp180_press_t)P))
|
|
||||||
{
|
|
||||||
// Failed to send info to user
|
|
||||||
printf("%s: Unable to inform user bmp180_informUser returned \"false\"\n", __FUNCTION__);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
}
|
||||||
|
|
||||||
// Default user inform implementation
|
// Default user inform implementation
|
||||||
|
|
@ -296,20 +312,13 @@ bool bmp180_init(uint8_t scl, uint8_t sda)
|
||||||
// 1. Create required queues
|
// 1. Create required queues
|
||||||
bool result = false;
|
bool result = false;
|
||||||
|
|
||||||
if (bmp180_create_communication_queues())
|
if (bmp180_create_communication_queues()) {
|
||||||
{
|
|
||||||
// 2. Init i2c driver
|
// 2. Init i2c driver
|
||||||
i2c_init(scl, sda);
|
i2c_init(scl, sda);
|
||||||
|
|
||||||
// 3. Check for bmp180 ...
|
// 3. Check for bmp180 ...
|
||||||
if (bmp180_is_avaialble())
|
if (bmp180_is_available()) {
|
||||||
{
|
// 4. Start driver task
|
||||||
// 4. Init all internal constants ...
|
if (bmp180_createTask()) {
|
||||||
bmp180_fillInternalConstants();
|
|
||||||
|
|
||||||
// 5. Start driver task
|
|
||||||
if (bmp180_createTask())
|
|
||||||
{
|
|
||||||
// We are finished
|
// We are finished
|
||||||
result = true;
|
result = true;
|
||||||
}
|
}
|
||||||
|
|
|
||||||
|
|
@ -52,4 +52,31 @@ void bmp180_trigger_pressure_measurement(const xQueueHandle* resultQueue);
|
||||||
// Give the user the chance to create it's own handler
|
// Give the user the chance to create it's own handler
|
||||||
extern bool (*bmp180_informUser)(const xQueueHandle* resultQueue, uint8_t cmd, bmp180_temp_t temperature, bmp180_press_t pressure);
|
extern bool (*bmp180_informUser)(const xQueueHandle* resultQueue, uint8_t cmd, bmp180_temp_t temperature, bmp180_press_t pressure);
|
||||||
|
|
||||||
|
// Calibration constants
|
||||||
|
typedef struct
|
||||||
|
{
|
||||||
|
int16_t AC1;
|
||||||
|
int16_t AC2;
|
||||||
|
int16_t AC3;
|
||||||
|
uint16_t AC4;
|
||||||
|
uint16_t AC5;
|
||||||
|
uint16_t AC6;
|
||||||
|
|
||||||
|
int16_t B1;
|
||||||
|
int16_t B2;
|
||||||
|
|
||||||
|
int16_t MB;
|
||||||
|
int16_t MC;
|
||||||
|
int16_t MD;
|
||||||
|
} bmp180_constants_t;
|
||||||
|
|
||||||
|
// Returns true if the bmp180 is detected.
|
||||||
|
bool bmp180_is_available();
|
||||||
|
// Reads all the internal constants, returning true on success.
|
||||||
|
bool bmp180_fillInternalConstants(bmp180_constants_t *c);
|
||||||
|
// Reads an optional temperature and pressure. The over sampling
|
||||||
|
// setting, oss, may be 0 to 3. Returns true on success.
|
||||||
|
bool bmp180_measure(bmp180_constants_t *c, int32_t *temperature,
|
||||||
|
uint32_t *pressure, uint8_t oss);
|
||||||
|
|
||||||
#endif /* DRIVER_BMP180_H_ */
|
#endif /* DRIVER_BMP180_H_ */
|
||||||
|
|
|
||||||
Loading…
Reference in a new issue