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Hi, I am looking for a missing pulse detector! Something like when +5V and 0V (Oscillator)the output is constant. If just any of the (5V or 0V) Constant Pulse, the Output should be Opposite.
Sorry my search word wantnt right. After posting I got the search word and I got the result. The same type of circuit. I was searching like On and off circuit detector, software hang detector, oscillator break finder etc(LOL).. Thanks for the help anyway..
The circuit that was linked to should work based on what you are asking. This circuit uses a 555 timer configured as a re triggerable one shot. As long as a steady stream of pulses comes into the 555 the output on pin 3 remains high. However, if there is a break in the pulse train the 555 output will go low.
Missing pulse detectors look at the PRT (Pulse Repetition Time) or Frequency of an incoming pulse train. In the linked to circuit the values of R1 and C1 determine the RC time. As long as incoming pulses are within the RC time the 555 output remains high but if a pulse is missing it goes low.
Now if you want the circuit to latch when an incoming pulse train is missing a pulse then the 555 output could be used to trigger a D flip flop (or other flip flop circuit).
What exactly are you trying to do? You don't mention the PRT of the pulse train you want to monitor? Maybe with a better detailed explanation you could get better suggestions.
Hello Ron,
The purpose of this is to detect the software runs fine in PC. As long as the S/W is working fine it will produce a 5V ON/OFF to port. When ever the S/W gets stuck it will produce eith 5V or 0V constant, then I want to pull in a relay for alarm. This is what I want to do. Any better suggestions!!
The circuit that was linked to should work based on what you are asking. This circuit uses a 555 timer configured as a re triggerable one shot. As long as a steady stream of pulses comes into the 555 the output on pin 3 remains high. However, if there is a break in the pulse train the 555 output will go low.
Missing pulse detectors look at the PRT (Pulse Repetition Time) or Frequency of an incoming pulse train. In the linked to circuit the values of R1 and C1 determine the RC time. As long as incoming pulses are within the RC time the 555 output remains high but if a pulse is missing it goes low.
Now if you want the circuit to latch when an incoming pulse train is missing a pulse then the 555 output could be used to trigger a D flip flop (or other flip flop circuit).
What exactly are you trying to do? You don't mention the PRT of the pulse train you want to monitor? Maybe with a better detailed explanation you could get better suggestions.
Hello Ron,
The purpose of this is to detect the software runs fine in PC. As long as the S/W is working fine it will produce a 5V ON/OFF to port. When ever the S/W gets stuck it will produce eith 5V or 0V constant, then I want to pull in a relay for alarm. This is what I want to do. Any better suggestions!!
What you want to do is not a problem and can be done. However, it starts with a software application. You have a computer running a dozen processes and have an interest in a single process. You want to know if the process is running or let's say stopped or hung. Let's say the operating system is Windows based. Windows keeps track of all running processes (programs). Therefore you need some software to query the operating system to see if the process you have interest in is running or stopped. The software code will query the operating system to see if the process is running or stopped and return a value of for example 1 or 0 where 1 = running and 0 = stopped. The code could also place a user message on the computer screen as well as send an output from a port to your hardware. That hardware would in turn trigger a relay or whatever you want it to do.
This all begins with software. I don't know of any other way to do what you wish to do. It is not that difficult but you need to be able to write some code to do it. Again, as I mentioned earlier you need to port the data from the computer running the process and software to your hardware be it a relay or whatever you have out there external to the computer. I would suggest a USB module with DIO (Digital In Out). The software needs to be written to run on the operating system you have, be it Windows based, Linux based or whatever is running the app you are wanting to look at.
See my reply to the other thread you have on this subject.
1- I have DIO port access controling my application for alarm etc
2- As you said- a software(B) will check whether the software(A) application is running. But when SW(A) stuck it will only give a output of either HI or LO. So software(B) have to check the HI-LO waves from SW(A) and then produce a O/P for any of the constant Wave from SW(A).
3- I came up with a circuit, it will OP a alarm when the IP is either steady HI or LO. Please see the circuit. Also try to close both the switch to see the effect. Circuit Simulator Applet
Thanks.
What you want to do is not a
problem and can be done. However, it starts with a software application. You have a computer running a dozen processes and have an interest in a single process. You want to know if the process is running or let's say stopped or hung. Let's say the operating system is Windows based. Windows keeps track of all running processes (programs). Therefore you need some software to query the operating system to see if the process you have interest in is running or stopped. The software code will query the operating system to see if the process is running or stopped and return a value of for example 1 or 0 where 1 = running and 0 = stopped. The code could also place a user message on the computer screen as well as send an output from a port to your hardware. That hardware would in turn trigger a relay or whatever you want it to do.
This all begins with software. I don't know of any other way to do what you wish to do. It is not that difficult but you need to be able to write some code to do it. Again, as I mentioned earlier you need to port the data from the computer running the process and software to your hardware be it a relay or whatever you have out there external to the computer. I would suggest a USB module with DIO (Digital In Out). The software needs to be written to run on the operating system you have, be it Windows based, Linux based or whatever is running the app you are wanting to look at.
See my reply to the other thread you have on this subject.
As Ken suggested, a watchdog timer is the way to go. This is the industry standard method to deal with hung sw. Typically the sw has to kick the dog (strobe) in a predetermined time or a reset is generated. The parts are very simple to use. **broken link removed**
If you already have everything then I would go with the watchdog timer family as was suggested. I have never used one but I am sure someone here likely has and can get you going with one. My read so far is you actually have a signal telling you of a program hang.
Hi, this problem can be solved in a couple ways. One way would be to use just AC couple the pulse to your missing pulse detector. That way, it would depend on the presense of a pulse, and not the level it gets stuck at.
As for the watchdog, if you're using a uController, it should already have one, and you just need to program it.
For my own sanity what I am totally missing is my understanding is this program is running on a computer as in everyday computer with an operating system that is Windows or Linux based. That is where I am likely screwing up and I am curious as all hell at this point.
For my own sanity what I am totally missing is my understanding is this program is running on a computer as in everyday computer with an operating system that is Windows or Linux based. That is where I am likely screwing up and I am curious as all hell at this point.
Hi Ron, A little more detailed explanation. I have a electronic device controlled by a custom S/W in c#( with DIO board). And the purpose of this missing pulse detector is to see whether the software is still running fine in the PC. So when no pulse or either steady Hi or Lo I want an alarm in the electronic device.
I think Ron wanted to know what kind of processor you're on and what, if any, operating system you're using. If you're running RTOS ( or no OS ) with a uController, you likely have a watchdog timer in the processor, and just need to program it. If you're running a multi-tasking OS ( Not likely from your vague description ) then it gets more complicated.
Hi, I am not using uControllers. I am using Windows based C# Appliction to control the DIO board. I think this Watchdog works fine, rite? https://www.electro-tech-online.com/custompdfs/2010/12/MAX6814.pdf Easy and simple. Just connect the In to the O/P from computer and O/P of chip to relay for alarm?
I think Ron wanted to know what kind of processor you're on and what, if any, operating system you're using. If you're running RTOS ( or no OS ) with a uController, you likely have a watchdog timer in the processor, and just need to program it. If you're running a multi-tasking OS ( Not likely from your vague description ) then it gets more complicated.
If you already have everything then I would go with the watchdog timer family as was suggested. I have never used one but I am sure someone here likely has and can get you going with one. My read so far is you actually have a signal telling you of a program hang.
Hi, I am not using uControllers. I am using Windows based C# Appliction to control the DIO board. I think this Watchdog works fine, rite? https://www.electro-tech-online.com/custompdfs/2010/12/MAX6814-2.pdf Easy and simple. Just connect the In to the O/P from computer and O/P of chip to relay for alarm?
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