Yoctopuce Yocto-Display, User Manual

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displayType
Display type: monochrome (MONO), gray levels (GRAY) or full color (RGB).
layerWidth
Width of the layers to draw on, in pixels.
layerHeight
Height of the layers to draw on, in pixels.
layerCount
Available layers to draw on.
command
Magic attribute used to send content to the display. If a command is not interpreted as expected,
check the device logs.
7.5. AnButton function interface
Yoctopuce application programming interface allows you to measure the state of a simple button as
well as to read an analog potentiometer (variable resistance). This can be use for instance with a
continuous rotating knob, a throttle grip or a joystick. The module is capable to calibrate itself on min
and max values, in order to compute a calibrated value that varies proportionally with the
potentiometer position, regardless of its total resistance.
logicalName
Character string containing the logical name of the analog input, initially empty. This attribute can be
modified at will by the user. Once initialized to an non-empty value, it can be used to access the
analog input directly. If two analog inputs with the same logical name are used in the same project,
there is no way to determine which one answers when one tries accessing by logical name. The
logical name is limited to 19 characters among
A
..
Z
,
a
..
z
,
0
..
9
,
_
, and
-
.
advertisedValue
Short character string summarizing the current state of the analog input, that is be automatically
advertised up to the parent hub. For an analog input, the advertised value is the calibrated measured
value (a number between 0 and 1000).
calibratedValue
Calibrated value of the anlog input, as an integer from 0 to 1000, included. If no calibration has been
run, the calibrated value is simply the measured value, scaled down to the range 0...1000, without
linearity correction.
rawValue
Measured value of the analog input, as is, formatted as an integer from 0 to 4095. The measured
value is zero when the input resistance is zero (closed contact), and reaches 4095 as the input
resistance moves toward infinity (open contact). Be aware that this value does not vary linearly with
regard to the input resistance (and to the known position). If you need a linear value, perform a
calibration and use the computed value
calibratedValue
.
analogCalibration
Use this attribute to start and stop the calibration process for the analog input. When the calibration
is enabled, the module records the minimal and maximal measured values into
calibrationMin
and
calibrationMax
. Once the calibration is over (stopped), the module can automatically
compute a running calibrated value for the every measure, varying linearly with the measured
resistance value.
7. Programming, general concepts
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