45 lines
1.1 KiB
ReStructuredText
45 lines
1.1 KiB
ReStructuredText
:mod:`ADC` --- A/D Converter input interface
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--------------------------------------------
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This module enables reading analog input values from the analog to digital
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converter (ADC) on the TI AM3358 SoC on the BeagleBone.
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Example::
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import Adafruit_BBIO.ADC as ADC
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ADC.setup()
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# The read method returns normalized values from 0 to 1.0
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value = ADC.read("P9_40")
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# The read_raw returns non-normalized values from 0 to 4095
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value = ADC.read_raw("P9_40")
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.. module:: Adafruit_BBIO.ADC
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.. function:: setup_adc()
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Setup and start the ADC hardware.
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.. function:: setup_read(channel)
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Read the normalized analog value for the channel.
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:param str channel: GPIO channel to read the value from (e.g. "P8_16").
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:returns: normalized value reading from 0.0 to 1.0
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:rtype: float
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.. function:: setup_read_raw(channel)
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Read the raw analog value for the channel.
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:note: Kernels older than 4.1.x returned a raw value range 0 - 1800
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based on the reference voltage of 1.8 V.
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:param str channel: GPIO channel to read the value from (e.g. "P8_16").
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:returns: raw value reading from 0 to 4095 (12 bits).
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:rtype: float
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