What are timers and counters?
Table of Contents
What are timers and counters?
It is a device that counts down from a specified time interval and used to generate a time delay, for example, an hourglass is a timer. A counter is a device that stores (and sometimes displays) the number of times a particular event or process occurred, with respect to a clock signal.
What are the functions of timer in PIC?
PIC microcontroller Timers:
- 8-bit timer/counter.
- Readable and writable.
- 8-bit software programmable prescaler.
- Internal or external clock select.
- Interrupt on overflow from FFh to 00h.
- Edge select for external clock.
Can timer be used as counter?
You can use timers as counters and your original suggestion using an external clock input ( that is the pulses you wish to count) is the way to go. If you have four flowmeters each one could be assigned to a seperate counter (timer) .
How many timers are there in PIC microcontroller?
three
PIC Timer Module Pic16f877a has three indepenndent timer which can be used as timer,Counters or for PWM generation.
What are timers used for?
The timer can be used to measure the time elapsed or the external events occurring for a specific time interval. They are used to maintain the operation of the embedded system in sync with the clock. The clock can be an external clock or the system clock.
What is counters and its types?
Counter is the widest application of flip-flops. It is a group of flip-flops with a clock signal applied. Counters are of two types. Asynchronous or ripple counters. Synchronous counters.
How do you calculate timer count?
The clock frequency is divided by 12 and used by the timer unit. Thus if a 11.0592MHz external crystal is used, the timer uses a frequency of 921KHz. Thus timer increments every (1/921Khz) = 1.085μ seconds. The C/Ṫ = 0 bit of TMOD register selects operation of Timer/counter unit as timer.
What is watchdog timer in PIC?
Simply put, the watchdog timer is a hardware timer in the PIC that, if not constantly reset by the software, will cause the PIC to reset. This feature can be incredibly useful if the PIC should hang due to a hardware or software issue and guarantees that the PIC will restart from the beginning.
Why timers are used in microcontroller?
The timer is an important application in Embedded systems, it maintains the timing of an operation in sync with a system clock or an external clock. The timer has so many applications such as measure time generating delays, they can also be used for generating baud rates.
What the different between timers and counters in PLC give simple example?
The timer is used to indicate that the input is turned ON/OFF or to create a delay. Counters are used to count the set of events that have occurred and the latch or unlatch is used to lock something ON or to turn it off.
What are timers in microcontroller?
What is a timer module?
A Timer / Counter module may derive its clock source from the system clock and perform counting operation based on this clock pulse. In this case it is said to work as a timer and perform time measurement operations.
What do you mean by counters?
1 : a piece (as of metal or plastic) used in reckoning or in games. 2 : something of value in bargaining : asset. 3 : a level surface (such as a table, shelf or display case) over which transactions are conducted or food is served or on which goods are displayed or work is conducted jewelry counter a lunch counter.
How is counter value calculated?
The obvious method is to feed the measurement signal into a counter chip which is turned on for a set period e.g. 1 second. The counter value is actually the frequency measurement since: f = events/time = counter value/1 second = counter value in Hz. A 100Hz input gives 3 digits etc.
What is period of a timer?
The timer period is the time it takes for the timer interrupt to occur. MCC just works out hidden variables so you don’t need to worry about the timer’s inner workings. For example: Let’s say you have an 8MHz clock going into the timer.
Should I turn off watchdog timer?
In many microprocessor applications where a watchdog supervisor, such as the TPS3306, is required, it may be necessary to disable the watchdog. This is particularly true when software boot times exceed the watchdog time-out period.
