68 lines
1.6 KiB
Markdown
68 lines
1.6 KiB
Markdown
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# BMP085 Module
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This module provides access to the BMP085 temperature and pressure sensor. The module also works with BMP180.
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## bmp085.init()
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Initializes the module and sets the pin configuration.
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#### Syntax
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`bmp085.init(sda, scl)`
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#### Parameters
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- `sda` data pin
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- `scl` clock pin
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#### Returns
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`nil`
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## bmp085.temperature()
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Samples the sensor and returns the temperature in celsius as an integer multiplied with 10.
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#### Syntax
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`bmp085.temperature()`
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#### Returns
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`integer` temperature multiplied with 10.
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#### Example
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```lua
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bmp085.init(1, 2)
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local t = bmp085.temperature()
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print(string.format("Temperature: %s.%s degrees C", t / 10, t % 10))
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```
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## bmp085.pressure()
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Samples the sensor and returns the pressure in pascal as an integer.
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The optional `oversampling_setting` parameter determines for how long time the sensor samples data.
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The default is `3` which is the longest sampling setting. Possible values are 0, 1, 2, 3.
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See the data sheet for more information.
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#### Syntax
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`bmp085.pressure(oversampling_setting)`
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#### Parameters
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- `oversampling_setting` integer that can be 0, 1, 2 or 3.
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#### Returns
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`integer` pressure in pascals.
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#### Example
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```lua
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bmp085.init(1, 2)
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local p = bmp085.pressure()
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print(string.format("Pressure: %s.%s mbar", p / 100, p % 100))
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```
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## bmp085.pressure_raw()
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Samples the sensor and returns the raw pressure in internal units. Might be useful if you need higher precision.
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#### Syntax
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`bmp085.pressure_raw(oversampling_setting)`
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#### Parameters
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- `oversampling_setting` integer that can be 0, 1, 2 or 3.
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#### Returns
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`integer` raw pressure sampling value
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