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What is high impedance pin?
Hi-Z (or High-Z or high impedance) refers to an output signal state in which the signal is not being driven. The signal is left open, so that another output pin (e.g. elsewhere on a bus) can drive the signal or the signal level can be determined by a passive device (typically, a pull-up resistor). Synonyms.
What is high impedance voltmeter?
In electronics, high impedance means that a point in a circuit (a node) allows a relatively small amount of current through, per unit of applied voltage at that point. High impedance inputs are preferred on measuring instruments such as voltmeters or oscilloscopes.
Why use a high-impedance voltmeter?
In order to measure correctly, you need the impedance of the voltmeter to be as high as possible so that very little current goes through it, so that it doesn’t disturb the circuit (the current that was going through the, for example, resistance that you are measuring voltage on will continue to be almost exactly the …
What is the input value of a high impedance pin?
This is called high impedance, or Hi-Z. The input value of a Hi-Z pin is defined by whatever it’s connected to. An unconnected Hi-Z pin is called a floating pin. The value of a floating pin (1 or 0) is unpredictable and undefined.
Is the GPIO pin in high impedance mode?
You have configured your pin correctly. The pin is in high impedance mode and will just have the leakage current as input current (in the order of microamperes). Reading the value of the pin will give you the logical value of the voltage applied to the pin. The voltage levels which correspond to a 0 or 1 are available in the devices datasheet.
What happens when a switch is high impedance?
When the switch is high impedance (an input), the a little bit of the power supply goes through the resistor and holds the pin high. This defines the high state (1), and we can say the pin is ‘pulled high’. Instead of being a random 1 or 0 when we read it, it will always be 1.
How does the MSP430 determine the voltage of a pin?
The MSP430 uses a Schmitt-Trigger at the input of each pin to determine whether the voltage represents a logic High (1) or Low (0). The datasheet specifies what to expect as far as logic thresholds.