diff options
| author | robert-hh <robert@hammelrath.com> | 2024-02-02 13:47:12 +0100 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2024-07-04 11:50:47 +1000 |
| commit | f36a5654a87838e68fb313272098777f76a94865 (patch) | |
| tree | 01a051faa647a92965ff3671ed1074d7421f05eb /docs | |
| parent | 2b8de7436bbdb54da99bf6bdb79359876fd3bc1d (diff) | |
docs/rp2/quickref: Document the use of channel numbers for ADC.
Signed-off-by: robert-hh <robert@hammelrath.com>
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/rp2/quickref.rst | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/docs/rp2/quickref.rst b/docs/rp2/quickref.rst index 11a808c11..ecf3f3186 100644 --- a/docs/rp2/quickref.rst +++ b/docs/rp2/quickref.rst @@ -187,6 +187,14 @@ Use the :ref:`machine.ADC <machine.ADC>` class:: adc = ADC(Pin(26)) # create ADC object on ADC pin adc.read_u16() # read value, 0-65535 across voltage range 0.0v - 3.3v +The argument of the constructor ADC specifies either a Pin by number, name of as +Pin object, or a channel number in the range 0 - 3 or ADC.CORE_TEMP for the +internal temperature sensor. If a pin is specified, +the pin is initialized in high-Z mode. If a channel number is used, the pin +is not initialized and configuring is left to the user code. After hard reset, +RP2040 pins operate in current sink mode at about 60µA. If the pin is not +otherwise configured, that may lead to wrong ADC readings. + Software SPI bus ---------------- |