Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
..
Counter: Counts and indicates the number of signals (events) input at any interval.
..
Timer: Counts the number of signals input at a constant interval to indicate the elapsed time.
A watchdog timer is a piece of hardware, often built into a microcontroller that can cause a processor reset when it judges that the system has hung, or is no longer executing the correct sequence of code.
Watchdog is a built in timer, this timer has to be refreshed periodically or else it will reset the microcontroller.
As a programmer it is your responsibility to refresh the watchdog timer within your program, so if your program is running properly then it will be refreshed. However, if your program hangs then the timer won’t get refreshed in time and it will reset your system.
A watchdog timer is a piece of hardware that can be used to automatically detect the system problem like fault condition, hang and send a trigger pulse to reset the system. You also can say it is a failsafe mechanism that can sense if a system stop functioning.
Generally speaking, a watchdog timer is based on a counter that counts down from some initial value to zero. The embedded software selects the counter's initial value and periodically restarts it. If the counter ever reaches zero before the software restarts it, the software is presumed to be malfunctioning and the processor's reset signal is asserted. The processor (and the embedded software it's running) will be restarted as if a human operator had cycled the power.
Timer Used for Delay operation or to Get the information in Precise Period. Whereas Counter Used For Counting the External Pulses from External World. Timer Can also be used for this but Programmers should take care of handling the timer to calculate the Pulses.
Difference between the two is
for Timer - The clock signal (Pulse) is genereted by known source were as for counter it will be gained externally, we may get one pulse per minute or one pulse per day. the time piriod of the pulse can,t be predicted in the case of counter.
A timer is a counter that counts clocks automatically and keeps track of time in seconds..
A counter is one that has to be made to count by the programmer whenever needed...
timer used internal clock of microcontroller for its clock,for measrin time intervals.
Counter use external clock,the external clcok may come from a sensor ,like as a flow transmitter sensor that measure flow of water ,it send for example 100 clock pulse per liter,
so counter is measuring quantity of some thing like as water .
In my view, timer and counter are both ticked by signal pulses. Timer typically uses the internal periodic clock sources, while counter may record discrete internal or external events. For timer, a proper ratio is set to make a tick as a second. Of course, counter also may have some overflow settings. If timer and counter can invoke the core to run some operations, then they can run as watchdog. Otherwise, programs should look up those event registers from time to time.
Am I right?
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
