Analog (analogue) and digital signals

Other Hardware General Electronics
1

Hi everybody,

I'm about to post a simple question, but I didn't found nothing on google.
Tell me if I'm wrong: a digital sensor can only return 0 or 1 (I'm not speaking about arduino, but in general electronic) and an analog (I'm writing a monograph in British English, and office says that 'analog' doesn't exist in the British English but only in the American one. Can I replace it with 'analogue'?) one can return a voltage that goes from 0 - minimum read - and 1 - maximum read; it works as a potentiometer that regulates itself reading physic aspects of the world? Am I right?

Thanks a lot!

Jymmy097

Edit: I found a Wikipedia article about Analog Signal, Analog signal - Wikipedia, sorry, the post can be canceled.

2

Umm, yes:
if (digitalRead(pinX) == HIGH){
Can use HIGH, LOW, 0, 1

analogValue = analogRead(A0); // returns 0 (0V) to 1023 (5V).
if (analogValue <= 400){ // Logic Low if less than 2V

if (analogValue >= 615 ){ // Logic High if more than 3V

I think that answers your question.

3

I do believe that the British spelling of analog is analogue. It means (in the context of your question)

relating to or using signals or information represented by a continuously variable physical quantity such as spatial position or voltage.

In general a digital sensor's output is going to be 1 value from a constrained (in size and range) set of values. In practice modern electronic digital circuits represent numbers with binary numbers, or numbers based on the power of 2. (Base 2) in that case there are 2 digits, 0 and 1. Look up binary numbers for more explanation.

So typically, an electrical analog sensor is going to represent what it is measuring with a voltage or current or frequency that can vary continuously across its range, and a digital sensor is going to output 1 number from a set of numbers that span its measurement range. If the digital sensor is a 1 bit sensor then the output can have two values, 0 or 1. If its an 8 bit sensor its output can have 256 values, but each digit is only 0 or 1. Once again read up on binary numbers to understand why an 8 bit binary number can have 256 values.

Regards, dougc314

4

In general, if something is called a "digital sensor", it means that it has an ADC (analog to digital converter) built-in, and it sends the information back as a (usually) serial data string. Not just a 1 or a 0, but a string of them representing a larger binary number.

5

An analog (or analogue) signal is one that represents (by analogy) a measured
value by some other physically measurable quantity (typically voltage/current/pressure/
frequency/force/position). It is not quantised like a digital value.

In British technical English the spelling "analog" has become widespread, just like "program",
"prolog" and "sulfur" (actually I think chemists actually decided that "sulfur" is the
international spelling for chemistry publications).

6

Although I spell and say "aluminum", I still love hearing someone say "aluminium".

7

Ok, lets get this back on track to digital vs analog discussion.

8

Jymmy097 needs to let us know if any of this has answered his questions.

9

I'm really sorry for the late.

Everyone helped me a lot. I'm writing a monograph about Artificial Perception and I need this information. Thanks a lot to everyone and sorry again: we had a lot to do at school this week.

Bye.

Jymmy097

10

Not quite polymorph, after all you can have a temperture limit switch that closes once a certain temperature is reached. An analog sensor with a digital output, as it were.

11

Which is why I said "in general". And the OP's question was, in part:

Tell me if I'm wrong: a digital sensor can only return 0 or 1