42 lines
1.4 KiB
Markdown
42 lines
1.4 KiB
Markdown
# Analog Read Pin
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Read an **analog** signal (`0` through `1023`) from the
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[pin](/device/pins) you say.
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```sig
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pins.analogReadPin(AnalogPin.P1)
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```
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### Parameters
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* ``name`` is a [string](/reference/types/string) with the name of the pin
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you say (`P0` through `P4`, or `P10`)
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### Returns
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* a [number](/reference/types/number) from `0` through `1023`
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This program reads pin `P1` and shows the number
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on the LED screen.
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```blocks
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basic.forever(() => {
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let value = pins.analogReadPin(AnalogPin.P1)
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basic.showNumber(value)
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});
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```
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#### ~hint
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If you are using **analog read pin** with another @boardname@ running **analog write pin**, then things can get tricky. Remember that the @boardname@ that runs **analog set pin** writes 0's and 1's at a very high frequency to achieve an average of the desired value. Sadly, if you try to read that average from another @boardname@, then the @boardname@ will either read 0 or 1023. You could try to read a higher number of values (e.g. a million) in a loop, then computer then average. Alternatively, you can plug in a capacitor in-between the two @boardname@s.
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#### ~
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### See also
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[@boardname@ pins](/device/pins),
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[on pin pressed](/reference/input/on-pin-pressed),
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[analog write pin](/reference/pins/analog-write-pin),
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[digital read pin](/reference/pins/digital-read-pin),
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[digital write pin](/reference/pins/digital-write-pin)
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