BMP180 Module¶
This module contains the driver for BOSCH BMP180 Digital Barometric Pressure Sensor. The ultra-low power, low voltage electronics of the BMP180 is optimized for use in mobile devices and the I2C interface allows for easy system integration with a microcontroller. The BMP180 is based on piezo-resistive technology for EMC robustness, high accuracy and linearity as well as long term stability (datasheet).
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class
BMP180(i2cdrv, addr=0x77, clk=100000)¶ Creates an intance of a new BMP180.
Parameters: - i2cdrv – I2C Bus used ‘( I2C0, ... )’
- addr – Slave address, default 0x77
- clk – Clock speed, default 100kHz
Example:
from bosch.bmp180 import bmp180 ... bmp = bmp180.BMP180(I2C0) bmp.start() bmp.init() temp, pres = bmp.get_temp_pres()
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init(oss=0)¶ Initialize the BMP180 calibrating the sensor and setting the oss value.
Parameters: oss – OverSampling Setting value (from 0 to 4), default 0
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set_over_sampling_setting(oss)¶ Sets the OverSampling Setting value of the BMP180.
Parameters: oss – OverSampling Setting value (from 0 to 4 allowed)
Note
The OverSampling Setting parameter selects different operating modes according to give the possibility for findind the optimum compromise between power consumption, speed, and resolution; in the table below allowed values are reported with related operating modes.
| OSS param | Operating Mode | N of samples | Conversion time | Avg Current 1 sample/s |
|---|---|---|---|---|
| 0 | Ultra Low Power | 1 | 4.5 ms | 3 uA |
| 1 | Standard | 2 | 7.5 ms | 5 uA |
| 2 | High Resolution | 4 | 13.5 ms | 7 uA |
| 3 | Ultra High Resolution | 8 | 25.5 ms | 12 uA |
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get_raw_temp()¶ Retrieves the current temperature data from the sensor as raw value.
Returns raw_t
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get_raw_pres()¶ Retrieves the current pressure data from the sensor as raw value; according to the OverSampling Setting value this measure can be faster but less accurate or more precise but slower. (see
set_over_sampling_setting())Returns raw_p
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get_temp()¶ Retrieves the current temperature data from the sensor as calibrate value in °C.
Returns temp
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get_pres()¶ Retrieves the current pressure data from the sensor as calibrate value in Pa; according to the OverSampling Setting value this measure can be faster but less accurate or more precise but slower. (see
set_over_sampling_setting())Returns pres
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get_temp_pres()¶ Retrieves the current temperature (in °C) and pressure (in Pa) data from the sensor as calibrate values in one call.
Returns temp
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get_altitude()¶ Calculates, from measured pressure, the current altitude data as value in meters.
Returns altitude
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get_sea_level_pres()¶ Calculates, from measured pressure, the pressure (in Pa) at sea level when given a known altitude in meters.
Returns p0 (pressure at sea level)