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Data range: 1g is approx. equivalent to a readout of 4096. The maximum is 4g, i.e. 16383. If the device is rotated by 180 degrees, the values become negative.
The axis orientation is:
Barometer and Thermometer
cat /sys/bus/i2c/devices/i2c-2/2-0077/pressure cat /sys/bus/i2c/devices/i2c-2/2-0077/temperature
Touch Screen Position, Pressure/Resistance, Temperature and (optional) Ambient light intensity
The raw ADC values, plate resistance, the temperature sensors and the AUX input (optional ambient light sensor) can be read through
The order of the values is
x, y, pressure, pendown(0/1), z1, z2, temp0, temp1, aux, resistance
The temp and aux values are updated every 100ms and the other values only on pen-down every 1ms.
Pressure values are an estimate and are lower for touches with small area (fingernail, stylus) and higher for bigger touch area (finger tip or multitouch). Typical range:
- 300 for stylus
- 700 for finger tip
- 2000-15000 for two fingers
Resistance is an estimate with a reference value of 600 Ohms.
Note: the x and y values are the raw values before any calibration (which is usually done through libts or similar means).