Hello all,

I hope this is the right forum to post this question.

As the subject line says, I'm looking to build a timer that can be adjusted (let's say between 10 seconds and one hour) and I want it to sound an alarm once the timer reaches zero.

In addition, I want my prototype to display the amount of time left.

What microcontroller and display controller would you pick if you had to build something like this?

One more thing - this device will be portable, so it must be battery-powered; at this point I'm thinking 3V but I'm willing to consider other options.
Any feedback would be appreciated.

 

The functions you want are very simple and can be handled with virtually ANY microcontroller out there..

Any reason you don't just buy an off the shelf timer? There are hundreds that do exactly what you want already..

What type of display do you want?
That will dictate the additional requirements/pin count/driver needs for that..

Do you have a preference on brand? AVR? PIC?,etc...
Do you have the programming tools?
Do you have a coding language of choice?
Do you have a development platform of choice?
Is this something that will go into production or just a one time hobby thing?

 

Thanks for the prompt reply!

This timer will have to function in conjunction with a sensor, so the overall functionality is a bit more complex than what I just described.

Any simple display will work. I just want to be able to display say - 1 minute to 60 minutes, so any two-digit LCD will work.

I have some experience with assembly code for PIC and Motorola processors. But that's from about two decades ago. I'm not even sure what dev platforms are available at the time so I'll have to look at that as well.

This device is intended to go into production.

As an alternative, I was thinking of handling all the timer/alarm part in a phone app, and have the sensor hooked up to a bluetooth transmitter that tells the phone/app whether it's on or off. That would mean fewer moving parts, less battery consumption and more flexibility.

Thanks again,
T.

 

One can't recommend anything properly without ALL the details..

YOU... need to specify number of I/O pins, ADC channels/bits, Flash size, bits, etc... (and 200 more questions)
Sounds like you should contact a suitable Engineer/Design Firm so they can nail down the specifics and design the product for you...

http://www.atmel.com/products/microcontrollers/default.aspx
http://www.microchip.com/pagehandler/en-us/products/picmicrocontrollers

 

You're 100% right.
I'll get back to work.
Thanks for the links!
T.

 

Hi tude.

Plenty of examples around, like this 4-Digit 99-Minute Timer featured in the Completed Projects sub-forum.

Cheerful regards, Mike

 

Mike, this is actually VERY close to what I need. I'll go look at that microcontroller's datasheet to see how I can hook up a sensor to it, and the rest is just software.
Thank you SO MUCH!
(now I'll go spend some more time in that sub-forum. Didn't know it existed! haha!)