Some time ago I made up a little quiz box that has a pair of arcade buttons on top, LM386 amp driving a small speaker, Nokia LCD on the front and an ATmega inside to keep score and play some tunes. What we've found is with the arcade buttons on top it gets hammered, and unfortunately spends a lot of time being repaired. It's back on the bench today, and I was thinking it might survive longer next time if I add an alternative way of hitting the buttons, that is wireless perhaps via key fobs...or using the arcade buttons I already have, but in a handheld wireless form.
There are a few subjects on this on this forum, but those projects don't appear to conclude. So my thoughts were I have lots of ATTiny85's laying about - if I got a couple of transmitter/receiver pairs (like these ones on eBay 433MHz and one 315MHz so there's frequency separation - is that necessary?) and hooked each up to an ATTiny I could move the arcade buttons each to a small cylindrical enclosure each with another ATTiny85 and battery in it to transmit. The receiving ones would just have to bring a pin LOW when they receive their code, and that pin would be attached to the ATMega pin that's currently grounded by the arcade button on the box.
For the cost of 4x ATTiny85's I already have, two short lengths of pipe, and the transmitter/receiver pairs I upgrade to wireless arcade buttons for probably $15-20 all up. Not having any experience with these what are your thoughts on the feasibility of this upgrade - especially but not limited to battery life expectancy at the transmitters? Am I right in thinking I need each on different frequencies to ensure the one that's closer or better batteries doesn't always win? And if you have a better/simpler thought it's early in the process so I'm completely open to alternative ideas.
If physical robustness is the only issue, I'd have thought that it should be possible to find/make an enclosure robust enough to withstand anything that you can do with your bare hands.
It would certainly be possible to add some wireless remotes to the solution but they will add substantial complexity, and you still have to make them robust enough to survive.
PeterH:
If physical robustness is the only issue, I'd have thought that it should be possible to find/make an enclosure robust enough to withstand anything that you can do with your bare hands.
It turns out we have some very competitive family members. I could as you suggest go more robust - and this time I was intending to upgrade to an anodized aluminium enclosure but am holding that thought as I don't think the wireless upgrade would be compatible with that. When the first enclosure got cracked the speaker came loose and shorted the 12V supply across the ATMega and the logic level IC resulting in the need for a new display, ATmega and CD4050. I subsequently drenched the inside with hot glue and most of the issues since have been broken wires, loose connectors and broken solder joints.
PeterH:
It would certainly be possible to add some wireless remotes to the solution but they will add substantial complexity, and you still have to make them robust enough to survive.
On the complexity side, since the arcade buttons take up the majority of the inside of the present project box I could replace it with the same size with the radio receivers, and likely have more space inside than I do now. And I'm hoping if the arcade buttons are thumb activated rather than being mashed from above, that setup shouldn't cop quite the punishment the box does now.
There are those anti vandalism buttons designed to endure a lot more than a competitive grandma and I can't think of anything more robust than a wire (well, perhaps a thicker wire?).
Or you could try capacitive touch detection. You need just a block of metal.