I am looking to augment a clipboard, such as the one pictured below, with an RTC and a stopwatch capable of being displayed simultaneously.
The clipboard has a flap as seen and this clock/stopwatch would be placed in the top right or left corner of the actual clipboard (not the flap). I would like it to be as small and flat as possible. A hole could be cut in the flap to accommodate it, but it still cannot stick out too much.
The stopwatch should be started, stopped and reset with a button push or similar, and display minutes and seconds, preferably not anything smaller.
I have searched for a ready made solution, but found none. As such, I turned to researching making it myself. I have searched for Arduino applications of this, but found none so far. How simple would this be for me to implement? I majored in Informatics and have worked for a few years as the only tech guy at a small radio station so I'm not entirely out of my waters, however I am more used to connecting cables than soldering and assembling. And my coding consists of a small amount of Java and SQL several years ago, but I imagine code for such rudimentary functions should be available.
How feasible is this project? Any ideas on how to go about it?
Flattest: flexible film PCB with additional components soldered on to it.
LCD screens can be really small and flat; make sure it connects over I2C and an ATtiny should be able to do all this. Some simple buttons and you're done. Just think of those tiny calculators and so.
Feasibility: total.
But for a one-off it's going to be expensive. Very expensive.
Expect couple hundred in USD. You're talking about custom PCB, prototyping manufacturing, etc - that's what makes it expensive. Should be possible to get down to 3-4 mm. On the other hand, produce 10,000 of them and your cost may drop to 1-2 USD a piece. No, this is not noob-friendly.
In the most noob-friendly version of this project that gets to a usable result you'll probably be soldering DIP packages on to a protoboard, without the sockets, and then you will get an overall thickness of 10 mm or more. You could maybe make it thinner by using a pro micro, without soldering the headers on. Should get you down to 6-7 mm.
That seems quite a ways outside my scope. I was looking to do this as a simple Arduino project, size is secondary, even tertiary, to simply having a functioning clock/stopwatch combination.
The alternative is to simply disassemble some off the shelf clock and stopwatch and rehouse them to fit the clipboard.
Did I misrepresent my intentions or is there simply no way to do this simpler and cheaper?
I have been searching for something like this, but so far no luck. Please share if you do! I live in Sweden, maybe some things exist but don't ship here.
Sobieski:
I would like it to be as small and flat as possible. A hole could be cut in the flap to accommodate it, but it still cannot stick out too much.
Sobieski:
That seems quite a ways outside my scope. I was looking to do this as a simple Arduino project, size is secondary, even tertiary, to simply having a functioning clock/stopwatch combination.
[...]
Did I misrepresent my intentions or is there simply no way to do this simpler and cheaper?
First you want it super small and fit inside a clipboard (so maybe 5 mm of space available), then it doesn't matter how big. So yes, it seems like you've misrepresented your intentions.
There are heaps of clock/stopwatch combinations out there. I bet many standard stopwatches have a clock built in already, and they're much cheaper than just the Arduino.
Building this from an Arduino is of course simple - but will you end up with a few parts and loose wiring in between. That's the nature of Arduino projects. You can put it in a box, it's not exactly big, though it's huge compared to an off-the-shelf stop watch which has been designed to be small.
