Silly question about timers

[eblc1388]

Why are counters in a PIC or other MCU called timers?

A real timer counts time elapses, timer don't have bits, so to speak.

They are really just counters, 8-bit or 16-bit presettable counters. All electronic parts with such function are correctly called counters, like 7490, 4040 or 4060...., have anyone ever seen a 4-bit binary timer? I have a frequency counter, it also measure time interval, but it is never called a timer.

 

[Papabravo]

Here is the distinction as I see it. In conventional usage a Timer is a counter that counts the periodic intervals of a fixed frequency clock.

A counter, on the other hand, counts events, which may or may not be periodic. This lack of periodicity is what separates the two applications.

That's just my opinion FWIW.

 

[eblc1388]

And the fact that a "timer" cannot be used to measure counts.
If something measure counts, it is by definition a counter.

 

[donniedj]

As Papabravo said, a counter is triggered and not a fixed interval of time. Though an MCU's timer may be triggered externally and also can be adjusted to a different interval at will, the timer is still is a specific interval and does occur in the background.

Disassemble a digital real timer. What do you find at its lowest core? Digital bits or quantum packs of time?

 

[philba]

to me the crux of it is that timers are counters driven off of a periodic source. You start a timer, then sample the count at a given point and that is the elapsed time in periodic units. Seems like a timer to me.

 

[Papabravo]

And the fact that a "timer" cannot be used to measure counts.
If something measure counts, it is by definition a counter.

OK...I'm not sure where you are going with this but you won't get either an argument or strong support for your position from me. Timers and counters are both great!

 

[Nigel Goodwin]

It's basically just two applications of the same hardware, if you go back to the 6502 and 6522 PIA days, they called them 'counter/timers'.

 

[eblc1388]

Just wondering if it is "politically correct" to call a 7490, 4040 or 4017 as a timer.

Anyway, this is a silly question and the answer is "who cares".

 

[Nigel Goodwin]

Just wondering if it is "politically correct" to call a 7490, 4040 or 4017 as a timer.

Not on it's own, but the 'timer' in a PIC isn't just a counter, it has extra hardware as well - so those counter chips, plus others, could be called a 'timer'

Anyway, this is a silly question and the answer is "who cares".

It's not as silly as many of the threads!