Greetings, friends. I'm in the first semester of college and I'm working on a project that means to show the user by a 16x2 LCD visor how many days, hours, minutes... until his/her next exam (a countdown timer) and the course of the exam, something like "4 days; 22 hours; 46 minutes until Calculus 1 exam". Unfortunately, as I said, I've just started college, so I'm actually counting on someone to help me with it. Thank you very much in advance.
We can help if you show what you have tried, which Arduino board you are using and which LCD module.
Do you have the components already?
If yes
1)
Which ones?
2)
Did you manage to get them working with simple example code?
If you don't have the components yet, what are you planning to use? Obviously a LCD and an Arduino (in some form). Have you considered how you will keep track of current time? Just a counter? Or maybe an RTC. Or maybe getting it of an NTP server?
@bruninzin May I suggest if you change the title to a more informative one you may get more useful help?
eg Arduino timer with 16*2 display?
I'm actually counting on someone to help me with it
The faculty should have put some learning in place surely, to guide you through this process. (eg, tutorials on how to think about the overall approach, and to get the various components going individually....) When I was a fresher we learned how to analyse trusses and once he had that down, we learned how to read the suppliers' catalogs and pick the right steel sections for the members and then design the bolted or rivetted joints. We were taught how to do those things. Sure, some took to it quicker and easier and needed less tutorial assistance, but the faculty did actually do some teaching. I doubt (had the 'net existed all those years ago) we would have hopped onto a structural steel forum and asked for help: we were paying for, and expected to receive, that help from the faculty.
Is this device going to be personally configurable for a specific user or are all the exam dates going to be on a central server and the user registers with your device and the next exam date, for that user, is displayed ?
If it requires a remote database / web server (say LAMP server) and registration (say RFID tags) it starts getting interesting. In any case, you probably want to develop a Web interface to it to enter exam titles and dates.
There have been other Forum Threads about countdown timers - suspect they will have most of what the OP needs.
For long term time-keeping (beyond a few hours) a Real Time Clock module will be essential - or WiFi for access to time on the internet.
...R
First off WELCOME TO THE FORUM !!!!
Generally, you would need a microcontroller, the UNO is a good start for a beginner.
since you are dealing with time, a RTC or Real Time Clock module would be useful. lots of tutorials available.
it would appear that you want to program it. there are some good videos by Andres on youtube showing menus
I would suggest you get
*a microcontroller
- RTC or a SD card shield that has an RTC on it.
- display
- dupont wires, male to male and female to female
- some LEDs
- some resistors. 1k, 330 ohms, 10k , and with those, you can make other values.
-some buttons and maybe an encoder (per the video)
you should be able to get the RTC working.
and get a menu working
and get the display working
then, the trick is to set a date and display the time remaining.
if you need help along the way, post your code. PLEASE read how to post code using code tags.
you will be able to do this in steps with all the tutorials and it will make sense as you learn and you may even want a larger display to show multiple future events.
dave-in-nj:
Generally, you would need a microcontroller, the UNO is a good start for a beginner.
Only if you are going to use it with "shields". Otherwise a Nano which can be used with a "solderless breadboard" or stripboard/ protoboard is much more practical. 
And cheaper in general. 
Paul__B:
Only if you are going to use it with "shields".
such as the recommended SD card shield with RTC ?
probably should have also said to get a 16x2 LCD shield with buttons. makes less work to get some results.
https://www.ebay.com/itm/223042019224
Just mentioning.
Those two shields would certainly do the job in this case. Reasonably neat, not absurdly expensive (well, not quite) from those sources as long as you are in the USA. Powered through the USB jack with a USB "phone charger". The display/ button shield has some dodginess.
In the more general sense, unless you have shields to do the job, a UNO is very inconvenient.
dave-in-nj:
probably should have also said to get a 16x2 LCD shield with buttons. makes less work to get some results.
https://www.ebay.com/itm/223042019224
That DFRobot DFR0009 style shield (apart from the dodginess just mentioned, mine exhibits that fault) is also a pin hog, since it uses 4-10 for the LCD. Adafruit have an I2C version: the screen and buttons are on the bus.
Yes, there's a problem with shields, are the two specified compatible in terms of which pins are used by each?
Fwiw, the pins exposed top right on the DFR0009 are (from right to left): 0, 1, 2, 3, 11, 12, and 13.
It also uses A0 for the buttons, with a resistor ladder.
This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.