Building a calculator

[Klaynos]

True' date=' it is fun.

 

I'd just get annoyed with all the repetitive soldering that making your own keyboard would mean. Of course, this is being said by the man who's spent the last month soldering together his 1024 LED matrix board, which is only a little over half way done. I'm just a little jaded [/quote']

 

I've always wanted one of them, too lazy to make one myself atm, might be a project for next summer though :s...

[YT2095]

might be a project for next summer though :s...

 

pick the right LEDs and do it Now, you can have "Summer" all winter long

[Thomas Kirby]

I hope you didn't have to draw that board by hand, mmalluck. It would make me crazy. These days what we really need are single LEDs that can change color and intensity according to a digital signal. Make them sort of like ICANs or something. Maybe even make them individually addressible so they can be controlled through the power line. Outfit them with phototransistors so they can sort of scan a horizontal line during the calibration phase.

 

I think that some suppliers have some smallish keyboards. The problem is finding one suitable for a handheld calculator, not finding a keyboard at all. If we were talking about microcontroller applications in general, a microcontroller that includes calculator functions and interface capabilities and has a graphics display can be really handy as a low power computer that can read sensors for a weather station, warn you if your freezer goes down or the door is hanging open, watch the furnace, display your E-mail, control your television and VCR, and use less than one watt of power. It can also just sit on your desk and be a calculator, one with your own programs and a display that is a lot more readable than my TI-89. It's really only difficult to get a small keyboard.