90 lines
2.4 KiB
Markdown
90 lines
2.4 KiB
Markdown
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# ICP1025 High-accuracy Barometric Pressure & Temperature Sensor <!-- omit in toc -->
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The ICP1025 library is intended to drive the TDK InvenSense ICP10125 temperature and pressure sensor.
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- [Getting Started](#getting-started)
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- [Taking A Measurement](#taking-a-measurement)
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- [Measurement Types](#measurement-types)
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- [Normal](#normal)
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- [Low Power](#low-power)
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- [Low Noise](#low-noise)
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- [Ultra Low Noise](#ultra-low-noise)
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## Getting Started
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Construct a new PimoroniI2C instance for your specific board. Breakout Garden uses pins 4 & 5 and Pico Explorer uses pins 20 & 21.
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```python
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import breakout_icp10125
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import pimoroni_i2c
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i2c = pimoroni_i2c.PimoroniI2C(4, 5)
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icp10125 = breakout_icp10125.BreakoutICP10125(i2c)
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```
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## Taking A Measurement
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The `measure` method triggers a measurement, blocks for enough time for the measurement to complete, and returns the result as a tuple with three values:
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1. Temperature (degrees C)
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2. Pressure (Pa)
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3. Status
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If the `status` is `icp10125.STATUS_OK` then the reading is valid. Otherwise you should probably discard it or attempt another reading.
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For example, the following code will continuously poll the ICP10125 for `NORMAL` readings and print them out if they are valid:
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```python
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import breakout_icp10125
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import pimoroni_i2c
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i2c = pimoroni_i2c.PimoroniI2C(4, 5)
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icp10125 = breakout_icp10125.BreakoutICP10125(i2c)
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while True:
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t, p, status = icp10125.measure()
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if status == icp10125.STATUS_OK:
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print(t, p)
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time.sleep(1.0)
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```
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## Measurement Types
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The ICP1025 has eight measurement commands. Four are supported by this library since the remaining four are identical save for the order of Temperature/Pressure data readout being reversed.
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Each measurement type has a fixed duration.
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### Normal
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Normal measurements are the default type, and take 7ms to complete offering a good balance of stability and speed.
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```python
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result = icp10125.measure(icp10125.NORMAL)
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```
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### Low Power
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Low-power measurements take just 2ms and trade stability for speed/power efficiency.
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```python
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result = icp10125.measure(icp10125.LOW_POWER)
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```
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### Low Noise
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Low-noise measurements take 24ms (roughly 3.5x as long as normal) and trade speed for stability.
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```python
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result = icp10125.measure(icp10125.LOW_NOISE)
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```
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### Ultra Low Noise
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Ultra Low-noise measurements take 95ms
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```python
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result = icp10125.measure(icp10125.ULTRA_LOW_NOISE)
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```
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