Create battery powered "timestamper" on button push

[cjscjs]

Hi,

I am looking to create a standalone circuit (battery powered) that can record the time (and date if possible) when a button was pushed. Assuming a button push outputs a 5V DC signal. Then would need to be able to retrieve this data from the circuit.


Any ideas where I could start or are there any existing solutions? A nice AC powered USB DAQ would be nice to use but too expensive and requires AC - but maybe there are some devices you know of that would be similar?


Thanks a mill,
CJS

 

[srikanthsamaga]

You can create one using a microcontroller, RTC and a memory (EEPROM or SD card).

You can retrieve the data by connecting it to a PC via serial port, if you use SD card and implement filesystem like FAT, you can connect the SD card to a card reader and retrive stored data.

 

[Reloadron]

Hi,

I am looking to create a standalone circuit (battery powered) that can record the time (and date if possible) when a button was pushed. Assuming a button push outputs a 5V DC signal. Then would need to be able to retrieve this data from the circuit.


Any ideas where I could start or are there any existing solutions? A nice AC powered USB DAQ would be nice to use but too expensive and requires AC - but maybe there are some devices you know of that would be similar?


Thanks a mill,
CJS

Does a PC figure into this? If you just want to have a puch button (normally open) and for each button press record the button press with a date time stamp it can very easily be done if the PC has a RS232 serial port using two pins of the port. The data is dumped into a text file. If you want to do this using a USB port it can be a little more difficult but can be done using a small piece of hardware for data acquisition between the PC and button.

Just a matter of exactly what you want to do and how you want to do it?

Ron

 

[alec_t]

Sounds like a standard data-logger (google for it) would be an off-the-shelf solution.

 

[cjscjs]

Hi - thanks for the 3 replies so far - awesome.

Reloadron - It has to be without a PC. I am going to build it into a unit that will house the button - and at some later stage retrieve the data. But I like the idea...

srikanthsamaga - this is nice and concise - I had been thinking microcontroller as a possibility so I'll see about persuing that route.

Alec_t - thanks. This is very interesting too. It might be that a solution off the shelf would be suitable. Have you any preference that you have used in the past? This is what I came across: https://www.microdaq.com/monarch/data_loggers/voltage-current-logger.php
Do you know of any cheaper modules that record voltage & timestamp like this one?


Thanks again all.
Chris

 

[Reloadron]

Hi Chris

The problem with using a data logger is getting a date/time stamp in there. When tethered to a PC running a date / time stamp with readings is an easy task. However, when a data logger runs stand alone then it becomes a problem. There are plenty of data loggers out there that will record data to a SD card or other storage media. The problem is they don't know the date and time to include it in the data.

One method would be a stand alone device using a GPS module to get the date / time data but things begin to go from simple to complex. Any other device would need an on board real time clock.

I do have a few data loggers laying around including a few stand alone versions. Let me look into what they can do.

Just My Take............
Ron

 

[alec_t]

Data-loggers with time/date stamping are well-known. See e.g. :-
https://www.google.co.uk/url?sa=t&s...sg=AFQjCNF54GRQBsYOzSzRBzbxXnkS8aU5Xw&cad=rja

 

[Reloadron]

Data-loggers with time/date stamping are well-known. See e.g. :-
https://www.google.co.uk/url?sa=t&s...sg=AFQjCNF54GRQBsYOzSzRBzbxXnkS8aU5Xw&cad=rja

Hi Alec, got a link to a make and model that is stand alone, and meets what the OP is looking for?

A nice AC powered USB DAQ would be nice to use but too expensive and requires AC - but maybe there are some devices you know of that would be similar?

I could not find any that are inexpensive (under a few hundred USD) that will include a date/time stamp function.

Ron

 

[cjscjs]

Hi All,

Thanks again for the additional replies. I had a look around the web and found 2 such data loggers that might suit:

https://www.dataq.com/products/hardware/el-usb-data-loggers/el-usb-5-data-logger.html#ordernow

and possibly https://www.microdaq.com/monarch/data_loggers/voltage-current-logger.php although this one is getting more expensive.


The EL-USB-5 seems like a nice fit. It has a built in RTC. However, one issue is battery life. I am looking to have a button monitored which might only be pushed < 10 times a day but for a sample rate of 1sec the battery is said to last maximum 9 hours. I was looking to investigate this button push for a few weeks which would be possible at lower sampling rates for that device but they would miss the button push. Many of these seem to be for monitoring temperature (typically a long time constant) and as alarms for going above or below a threshold.

Reloadron - the issue with having a PC is the trailing cables. The button will most likely be on a moving cart and cables would be hazardous and limit the mobility of the cart. One possible solution might be that the button push would broadcast to a nearby PC with this date/timestamp feature which could be plugged in. But because of the location of where the button will be, that would render the PC only having a single function which puts up the price - although I might have an old monitorless laptop lying around that might suit.

Any comments would be appreciated or what your experience has been.


Thanks,
CJS

 

[cjscjs]

Think I have a datalogger with sufficient battery life...

Hi All,

Ok, I think there was a mix up in the specifications for the datalogger in terms of battery life.

From here: https://www.electro-tech-online.com/custompdfs/2011/08/0900766b80e7c562.pdf

There are more clear specifications in terms of battery life. The datasheet states in the table footer of page1 that the battery life is 1 year for 1 event every 5 minutes, with voltage input mode. This might do the trick. I wouldn't expect any more use than that - if even.

Any thoughts? Is there anything I am missing do you think?

Thanks,
Chris

 

[Reloadron]

The first unit you linked to should have an average battery life of about a year. Any of these devices I would have a battery life dependent on use.

Funny is that the first linked to unit is distributed by a company called Dataq which is about a few miles up the road from my location. I use many of their data logging devices. I am guessing when you set the logger up it counts forward from the date and time you enter. Pretty slick and at under $100 USD a pretty reasonable little unit. These units are all the same, if US then I would order from Dataq, if Euro then the second link. They are EL-USB-5 Event, Count, and State Data Logger so whatever is more convenient. It will do what you want it to do.

Ron

 

[cjscjs]

Nearly (if not) Decided...

Just up the road - strange!

Thanks for the info Ron and your take. Appreciate it. I think this is the unit I will go with. It should give battery life span of a year with moderate use (up to ~105k events assuming one event every 5 mins).


Thanks for all the comments.
Chris

 

[alec_t]

Hi Alec, got a link to a make and model that is stand alone, and meets what the OP is looking for?

Nope. Clearly the OP has Googled as I suggested

 

[Reloadron]

Nope. Clearly the OP has Googled as I suggested

Yeah, and on a global basis, one of the distributors is literally in my back yard and I use their products. Go figure!

Ron