Hack a business calculator today

Do you own, or have access to, a HP 20b business calculator? Your assignment for today is to sincerely intend to hack it, even if you have no means to do so. From Make:

The latest HP 20b biz calc can be modded' (they're releasing a dev kit). I downloaded the dev kit, they're not messing around, schematic is included. Gang, this is an Atmel ARM, an LCD with the power supply done - what the heck is going on here? Way over powered for a calc, just asking for projects - Makers please do something cool with this!

Follow the link to view intimidating schematics. Here are some alternative calc uses anyone can perform:

1. Hammer hack! Bang a picture hook into drywall with one.
2. Steadying a wobbly chair or table. Recommended for use only with already-broken calculators, especially if you are overweight.
3. Amusing other young men by punching in 55318008 and turning it upside-down.
4. Amusing yourself by pushing gently on the LCD to bring the oily liquids to the surface. Ah, the transitory nature of beauty.
5. Social engineering hack! Leave others' calculators in special modes, to annoy and frustrate them when they just want to figure out a tip. Fifteen percent of $13.44 is 00C9.

HP 20b bix calc can be modded [Make]

[#1 posted by A New Challenger , August 19, 2008 9:01 AM]

There's an extraneous 5 in #3 above.

Sadly, that trick lost its novelty once we all got graphing calculators and could just use letters. But when the calculator god closes a door, he opens a window- the window in this case being graphing in polar coordinates.

[#2 posted by Rob Beschizza , August 19, 2008 9:26 AM]

Au contraire! The extra 5 allows one to utilize all the characters on a traditional cheap calculator, suggesting the hilarious word "Boobless."

[#3 posted by dculberson , August 19, 2008 10:25 AM]

Man! I got all excited, thinking "I have one of those!" But no, mine is a lame-o 10B II. :-(

I'll have to seek out a 20b and see what fun can be had.

[#4 posted by Anonymous , August 19, 2008 10:57 AM]

Does the dev kit explain why a business calculator has trig functions on it?

[#5 posted by nprnncbl , August 19, 2008 1:18 PM]

Then it should be 55378008, right?

34343434

[#6 posted by rAMPANTiDIOCY , August 19, 2008 5:39 PM]

what kind of moron needs a calculator to figure out a tip . . . especially such a round percentage as 15. jesus!

[#7 posted by mdhatter , August 19, 2008 5:56 PM]

Curses!

[#8 posted by dculberson , August 19, 2008 6:52 PM]

15 is "round?" I mean, I guess so, it's relatively easy to calculate...

[#9 posted by Halloween Jack , August 20, 2008 10:57 AM]

Isn't this sort of like modding a classic Pong game so that you can put a little English on the ball?