So you're a programmer deciding where to invest your energy. What's a better idea: the latest Apple device, where hot new games can mean big bucks and millions of users, or a calculator introduced 10 years ago?
Most go for iPhones and iPods. But another community thrives in its own way. These are the folks who spend hours trying to elevate their Texas Instruments calculators to a level far surpassing their modest roots.
Among their achievements: adding new features, creating new operating systems, connecting the calculator to keyboards and other hardware, playing a video excerpt from "The Matrix," and even running Nintendo Game Boy video games. Not bad for calculators such as the $100 TI-83 Plus, introduced in 1999 with a Z80 processor running at 6MHz, 24KB of memory, 160KB of flash memory, and a 96x64 pixel display.
Why all this work for projects that realistically are not going to reshape the future of computing? Much of the motivation parallels mountaineer George Mallory's rationale for climbing Mount Everest: "Because it's there."
TI's graphing calculators are programmable, affordable, and widely used in schools--a lot more approachable than a Himalayan peak. That doesn't mean they're easy. The calculators must be programmed in assembly language--a slightly more human-readable version of the very basic machine code the calculators execute, but hardly something more easily read and debugged such as C or Java.
'Squeeze to get the juice'
Although TI calculator hackers may be an uncommon breed, plenty of people relish a good challenge.
Dan Englender, a 26-year-old in Washington, D.C., who was very active in TI hacking for years and wrote the MirageOS for the calculator family, enjoys the challenge. "They're kind of fun to play with as they come from the factory, but they're even more fun when you make them do stuff they weren't designed to do," he said. "It's remarkable what you can squeeze out of those calculators...but you have to really squeeze to get the juice."
Adds Michael Vincent, "The motivations for this sort of work are largely challenge with some utility mixed in. For me personally, my hacking efforts were all about achieving what has previously been impossible." Vincent in 2002 wrote the CEPTIC operating system for the TI-83 Plus and now is news editor for the ticalc.org site.
For Brandon Wilson, exploring every last nook and cranny of a TI calculator is part of the appeal.
"For me it's figuring out something new," said Wilson, a 25-year-old programmer at a call center in Elizabethton, Tenn. He's been using TI calculators since seventh grade, developed a way to install third-party operating systems on the calculator earlier this year, and now is writing his own. "There's a lot of satisfaction being able to understand something so completely. It's very rewarding, at least for me."
And as with mountaineering exploits, there's also some measure of recognition.
One high point for Englender came during dorm-dweller introductions in his freshman year of college. Upon hearing Englender's name, one fellow approached him. "'You're Dan Englender? You wrote MirageOS?' They had heard of me and knew of my software, which was unexpected and gratifying," he said.
That recognition is part of the social element of TI calculator hacking. As with open-source software development, some people enjoy being part of something bigger than themselves.
The community ties were on display earlier this year when one person, Benjamin Moody, revealed that he'd cracked the 512-bit digital key used to sign the operating system on the TI-83 Plus calculator after a three-month brute-force calculation effort on his PC.
"Once that was released, a community effort was set up to factor the remaining keys for all of the other calculators. Hundreds of people joined in the effort after I posted news about it on ticalc.org," Vincent said. "With hundreds of computers cracking, it took but about a month to crack all remaining keys for every model of calculator."
Making a difference
It's not all an academic exercise. Calculators often are permitted in schools that ban mobile phones and gaming devices, so calculator games can be popular. Among the options are Tetris, Mario Brothers, Sonic the Hedgehog, car racing, and some role-playing games.
Those programs can be a bane as well as a boon. "I was teacher for two years. I know I removed games from calculators in my classroom. It's a distraction for students," Englender said.
Hacked calculators also can open up new possibilities for their intended purpose, performing mathematical calculations.
"The difference between a low-end calculator and a high-end calculator is 99 percent software. While the TI-89 series is faster and has more memory than the TI-83 Plus, that in itself is not the reason why the TI-89 is more advanced," Vincent said. Adds Englender, TI has calculators for middle school, high school, and college, but the college student might not want to drop another $150 for a new model.
And there's something personal to gain, too. Wilson believes he's a better programmer as a result of his TI hacking.
Texas Instruments, which didn't respond to a request for comment for this story, doesn't embrace the hacking community or its results. Most recently, they sent letters demanding that people remove the operating system signing key from their Web sites. Wilson was among those to receive the letters, which said the programmers were violating the Digital Millennium Copyright Act. Having the signing key makes it easy to install an alternative operating system on a calculator; software efforts before that relied on complicated installation methods or running software atop TI's operating system.
Some complied with TI's demand, but while the company may have won a battle, it may yet lose the war. The Electronic Frontier Foundation argues TI's DMCA letters are baseless, and some TI calculator hackers represented by the EFF plan to republish their posts later this month.
So how did it feel to receive the letter?
"I certainly felt bad," Wilson said, but he's not deterred. "I've been deeply involved in this community for a long time. It's important to me. I'm not going to stop just because of one DMCA notice," he said.
Perhaps perversely, TI's stance also is something of an incentive. "That's part of what makes it fun. There's no company that helps you. You're on your own," Wilson said. "TI and the community have a long history of not helping each other."
Vincent expected some legal action from TI, but not at the scale they actually took that action.
"I was very surprised that they blanketed the Web with them, sending them to bloggers who merely linked to ticalc.org or to other Web sites describing the crack," Vincent said. "I felt that TI shot themselves in the foot by turning this into a huge event."
TI hasn't always been a roadblock, though.
Englender, who saw the DMCA letters as "corporate bullying," was also around when TI voluntarily released the digital key needed to sign calculator software.
"Originally when they released the TI-83 Plus, you had to pay, like with Apple, a developer fee and had to download the software developer kit. Before you could release the application you had to send to TI and they would approve or deny it," Englender said. "At some point they decided to give out the application signing key. That was a wonderful gesture to the development community."
Though the calculator community remains vibrant, Englender--who has stepped back from active TI calculator hacking himself--can see a time when newer challenges such as mobile phones or Web-based applications hold more appeal.
"Cell phones are becoming increasingly powerful and accessible to programming," Englender said. "People who would otherwise have been interested in hacking calc because it was accessible might want to hack their iPhone or BlackBerry or Palm Pre."
Correction 6:10 p.m. PDT: This story incorrectly attributed a quotation about climbing Mt. Everest. George Mallory said the words, "Because it's there."