Zilogic Systems ZIO User Manual page 16

ZIO, Motherboard User Manual
potentiometer is moved from pin 1 to pin 3, the raw value varies from 0 to N
given by the following formula.
N = (0xFFFF x R
max max
Here,
• R is the maximum resistance of the potentiometer
max
• 10K is the internal pull up resistor on the Sensor signal. For more details refer ???.
For a 10K potentiometer, N
Connecting a Resistive Sensor.
measured are called resistive sensors. Examples of resistive sensors are Light Dependent Resistor
(LDR), thermistor, etc. These sensors can be directly connected between the Sensor signal and
GND . As the parameter being measured varies, the resistance varies accordingly, and the raw value
(N) produced is given by the following formula.
N = (0xFFFF x R) / (R + 10K)
Here,
• R is the resistance of the sensor
• 10K is the internal pull up resistor on the Sensor signal. For more details refer ???.
An example circuit, using the LDR, is shown below.
4.2. Voltage Sensors
Voltage measurement, -3V to +3V.
measure voltages between -3V and +3V using a simple circuit. The circuit diagram is shown in the
figure below.
) / (R + 10K)
max
= (0xFFFF x 10K) / (10K + 10K) = 0x7FFF
max
Sensors whose resistance varies with the parameter being
Though the ADC input range is 0 to 3V, it is possible to
Zilogic Systems
Rev. 2.0
. Where N is
max max
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