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Interfacing to External Devices. Explore Digital Interfaces techniques Introduce some complex optical devices and how to interface them Describe methods for switching devices on and off. Interfacing Digital Input Signals. General requirements of all digital input signals:
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Interfacing to External Devices Explore Digital Interfaces techniques Introduce some complex optical devices and how to interface them Describe methods for switching devices on and off
Interfacing Digital Input Signals • General requirements of all digital input signals: • The voltage input level should only be the legal allowed voltage. • They should not be corrupted by glitches • They should switch cleanly and fast.
Switch Debouncing • Switch debouncing happens when mechanical contacts switch and thus from the force of the switching they bounce for a few milliseconds.
Shaft Encoders Angular Speed S = output frequency / number of holes revolutions per second This setup does not give indication of direction
Semiconductor H-Bridge 2 http://www.dprg.org/tutorials/1998-04a/