Shortcut to switching off a calculator.

November 24, 2007 4:47 PM

I've found that I can switch off most calculators without an "Off" button, by simultaneously mashing buttons and pressing "On". (I usually hold down "5" and "6", then press "On".) Can someone explain to me why and how this is possible?
posted by Xere to Grab Bag (8 answers total)

Best answer: Has something to do with ghosting. Probably the microcontroller is either programmed to turn off if it detects something funny with the keyboard, or there's an "off" key programmed that isn't present on your keyboard, but you can ghost to it.
posted by trevyn at 4:55 PM on November 24, 2007

Is it just "pocket mode"? So that stray keypresses don't run down the battery?
posted by misterbrandt at 5:42 PM on November 24, 2007

Weird. On the cheap calculator sitting on my desk 2-3-ON, 3-2-ON and both permutations of 5-6-ON turn off the calculator. Most other numerical combinations don't seem to work, but I'm not going to try every single one.

This is a pretty non-standard calculator. The cheap corporate gift type (very cheap).
posted by Orange Pamplemousse at 6:13 PM on November 24, 2007

5-6 and on turns off my dollar store solar calculator THAT HAS AN OFF BUTTON! I had no idea. And now I love it.
posted by Ohdemah at 6:31 PM on November 24, 2007

Curious: Why turn off a calculator? (Or is yours not solar-powered?)
posted by dmd at 8:11 PM on November 24, 2007

Curious #2: why not just turn it off?
posted by Carol Anne at 6:03 AM on November 25, 2007

My Casio MS-80TV (generic office supply without Off button) doesn't seem to have a function like this. Rest assured that I'm going to test every calculator I come across for the rest of my life. Thanks a lot.
posted by lizzicide at 7:33 AM on November 25, 2007

Response by poster: #1: For the paranoid college student, enrolled in Math class and with a borrowed calculator with unknown battery levels and no solar power source ... this "off" method feels safer.

#2: Some calculators don't have "Off" buttons.
posted by Xere at 10:12 PM on November 26, 2007