Difference Between Timer and Counter

Timer vs Counter
 

Keeping track of the numbers and counting is one of the fundamental thoughts of the human civilization. It is often regarded as the origin of mathematics. As civilization advanced, methods for counting also advanced. However, it clearly exceeded the human capacity and methods were invented to make the process automatic.

With the industrial revolution, mechanical counters were developed to be integrated into the new machines. From the 20th century, when machines were developed with electronics, the timers and counters were also implemented easily with electronics.

More about Counter

A logic circuit designed to count the number of a specific event in relation to a clock signal is known as a digital counter. Counters are sequential logic circuits which use flip-flops as the building blocks.

The simplest type of counters is the asynchronous counters made using JK flip-flops. They use the output from a JK flip-flop as the clock of the next flip-flop, and this creates a ripple effect, where each flip-flop is enabled at the increasing number of pulses. This allows the counter to keep the number of counts as the clock signal continues. Theses counters are also known as ripple counters because of this functionality, and since the flip flops are set or reset (the data bits change) at different positions they are also known as asynchronous counters.

Counters can be designed to operate with data bits changing at the same instant in every flip flop of the counter. Such a counter is known as a synchronous counter, and they share a common clock to achieve this functionality. Decade counters are adaptations from above two counters, where the flip-flops or the register counting is reset when the bit configuration for 9 is present in the registers. In Up/Down counters, the counting progresses either in ascending or descending order. Ring counters are composed of a circular shift register where the output of the final shift register is fed back as the input of the first register.

More about Timer

A counter can be set up to count time intervals, such as the clock pulses. For example, a clock pulse with a duty cycle of 500ms will count 1s per cycle. This idea can be extended into much smaller or larger time scales.

Keeping track of time is important in every device; as such, almost all the electronic devices have a hardware timer. In computers, a hardware timer is inbuilt, and for additional purposes, software timers are maintained based on the fundamental hardware timer.

One other special type of timer is the watchdog timer, which is a timer that resets the corresponding system whenever a fault, malfunction, or a system hang is detected.

What is the difference between Timer and Counter?

• A counter is a device that records the number of occurrences of a particular event. In modern applications, counters are based on electronic devices and the counters are sequential logic circuit designed to record the number of electric pulses fed into the counter.

• A timer is an application of the counters where a certain signal with a fixed frequency (hence period) is counted to record the time.