# difference between timer and counter

Discussion in 'General Electronics Chat' started by nickmomo, Sep 20, 2008.

1. ### nickmomo Thread Starter New Member

Sep 20, 2008
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hi , anybody can establish the real difference between timer and counter?

2. ### mik3 Senior Member

Feb 4, 2008
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Basically, a timer can produce time delays (monostable operation) or continues pulses (astable operation) and a counter can count from zero up to a number or from a number down to zero every time it gets an input signal.

3. ### hgmjr Retired Moderator

Jan 28, 2005
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Often these two functions are consolidated into one device. These devices have the capability to derive their clock from an internal oscillator when used in the timer mode or they can take their clock source from an external signal in which case it behaves as a counter.

hgmrj

Mar 24, 2008
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5. ### scubasteve_911 Senior Member

Dec 27, 2007
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I thought they were the same
A lot of times, timer/counter are interchanged in the industry. Although, that doesn't make it correct, just misleading.

6. ### Wendy Moderator

Mar 24, 2008
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It can be confusing. Since the term has been around a very long time, and actually describes several different classes of circuits it is probably a good idea to add a preface word to narrow it down. For example a digital timer uses flip flops, a digital second timer would likely have a numberical display. The oldest definition is something I've been working on for a submission.

7. ### Papabravo Expert

Feb 24, 2006
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The hardware for a timer and a counter are the same. The distinction is in the input source. If the input is a signal with a known, constant period, then the hardware is being used as a timer. In other word you can establish a 1-to-1 correspondence between edges and elapsed time.

If the input signal is aperiodic then you are using the hardware as a counter. In this case you cannot establish a 1-to-1 correspondence between edges and elapsed time.

8. ### scubasteve_911 Senior Member

Dec 27, 2007
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Papabravo,

That makes perfect sense! Thanks for clearing it up

Steve