41 lines
1.9 KiB
Python
Executable File
41 lines
1.9 KiB
Python
Executable File
# Copyright (c) 2014 Adafruit Industries
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# Author: Tony DiCola
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# Permission is hereby granted, free of charge, to any person obtaining a copy
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# of this software and associated documentation files (the "Software"), to deal
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# in the Software without restriction, including without limitation the rights
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# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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# copies of the Software, and to permit persons to whom the Software is
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# furnished to do so, subject to the following conditions:
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# The above copyright notice and this permission notice shall be included in all
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# copies or substantial portions of the Software.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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# SOFTWARE.
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from . import common
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from . import Raspberry_Pi_Driver as driver
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def read(sensor, pin):
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# Validate pin is a valid GPIO.
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if pin is None or int(pin) < 0 or int(pin) > 31:
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raise ValueError('Pin must be a valid GPIO number 0 to 31.')
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# Get a reading from C driver code.
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result, humidity, temp = driver.read(sensor, int(pin))
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if result in common.TRANSIENT_ERRORS:
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# Signal no result could be obtained, but the caller can retry.
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return (None, None)
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elif result == common.DHT_ERROR_GPIO:
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raise RuntimeError(
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'Error accessing GPIO. If `/dev/gpiomem` does not exist '
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'run this program as root or sudo.')
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elif result != common.DHT_SUCCESS:
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# Some kind of error occured.
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raise RuntimeError('Error calling DHT test driver read: {0}'.format(result))
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return (humidity, temp)
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