Is discrete input signal still raw after it is debounced ?

Thread Starter

naseeam

Joined Jan 4, 2017
33
Consider a typical Automotive Embedded Software System.

A discrete input signal is 0 or 1. An example of discrete input is ignition ON or OFF.

After discrete input signal is debounced or a state change is latched, is discrete input signal still raw value?

Second question: Should Electronic Control Unit (ECU) low level software debounce discrete inputs or just read the real time state of discrete input? Are there any exceptions meaning some discrete inputs should be debounced, whereas others don't need to be debounced?
 

Papabravo

Joined Feb 24, 2006
14,233
Debouncing is done when there is a mechanical switch that makes and breaks multiple times as the contacts engage and disengage. If the digital input is coming from a source that is not derived from a set of actual switch contacts then debouncing would seem redundant.
 

Thread Starter

naseeam

Joined Jan 4, 2017
33
By "raw value" I mean discrete input signal coming into microcontroller is as is, it has been conditioned or modified.
 

nsaspook

Joined Aug 27, 2009
7,469
By "raw value" I mean discrete input signal coming into microcontroller is as is, it has been conditioned or modified.
That's as clear as mud. For a bool variable there are only two values/states while the raw electrical input signal to the micro-controller could have a very large range of values the debounce function reduces to a bool as a factor of time and present state.
 

ErnieM

Joined Apr 24, 2011
8,053
If "raw value" means "as is" then the debounced signal is not a raw value.

Do I get a prize for playing the overly pedantic definition game?


[/insert Gordon Ramsey Joke here]
 
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