29-Oct-09: TI & Calculator Hackers

While it’s not vintage calculators at play here, I came across the following article today that is definitely interesting. There is relatively small but dedicated group of folks that have a keen interest in hacking calculators. The calculator make of choice for hacking is the TI 84+, a very capable calculator made by Texas Instruments. The article talks about a calculator hacker that figured out the keys to the encryption scheme that protects the TI 84+’s firmware from modification. Once these keys were hacked, it is possible to make changes, or even completely replace the firmware that forms the operating kernel for the calculator. Quite an amazing accomplishment.

However, Texas Instruments is not taking this at all well. The company’s legal department has sent DMCA (Digital Millennium Copyright Act) cease-and-desist letters to a number of folks who posted details and mods online for the TI 84+. In response, the Electronic Freedom Foundation (EFF) is backing the calculator hackers, stating that there is no harm in their activities since TI makes the code for the calculator available for download.

The article can be seen at: IEEE’s Spectrum Online Magazine.

Hacking calculators is not new. Back in the old days, a lot of modifications were made to calculators to augment or improve their function. In the days of mechanical adding machines, contraptions were built that used solenoids to activate keys on the keyboard to automate data entry and problem solving, with the printing action of these machines recording the results. Sometimes such modifications were used to make inexpensive numeric printers. Benson-Lehner made modifications to a Friden rotary electromechanical calculator to interface it to an electric typewriter that allowed the calculator to serve as a math unit for a system, called the Computyper, that would perform functions such as invoicing. Once electronics came on the scene, necessity being the mother of invention, all kinds of hacks were developed to allow the machines to be programmed or automated in various ways. Some calculator manufacturers would make machines that had chipsets that had more capability than the function keys on the keyboard allowed. This was done to provide a line of calculators with different functions depending on how many keys were available on the keyboard, and how the keys were wired. By rewiring keys, or adding additional keys, folks could access these additional functions. Folks also used scientific calculator chips as peripherals on early home computers to act as math co-processors.

With today’s calculators essentially being computers with LCD displays, USB and serial connectivity, flash memory for firmware storage, and lots of keys on the keyboard, it seems only natural that folks would want to customize their machines to their liking. While the author won’t condemn TI for their action, nor condone the activities of the “hackers”, it just seems to me that this making a big deal out of something that is a natural tendency of bright folks to do. Let’s hope that this all settles on its own and doesn’t result in a big waste of time and money for all parties involved.

Leave a comment