Shipping Your Illicit Software On Launch Hardware

June 13, 2024 by Navarre Bartz 17 Comments

In the course of a career, you may run up against projects that get cancelled, especially those that are interesting, but deemed unprofitable in the eyes of the corporate overlords. Most people would move, but [Ron Avitzur] just couldn’t let it go.

In 1993, in the midst of the transition to PowerPC, [Avitzur]’s employer let him go as the project they were contracted to perform for Apple was canceled. He had been working on a graphing calculator to show off the capabilities of the new system. Finding his badge still allowed him access to the building, he “just kept showing up.”

[Avitzur] continued working until Apple Facilities caught onto his use of an abandoned office with another former contractor, [Greg Robbins], and their badges were removed from the system. Not the type to give up, they tailgated other engineers into the building to a different empty office to continue their work. (If you’ve read Kevin Mitnick‘s Ghost in the Wires, you’ll remember this is one of the most effective ways to gain unauthorized access to a building.)

We’ll let [Avitzur] tell you the rest, but suffice it to say, this story has a number of twists and turns to it. We suspect it certainly isn’t the typical way a piece of software gets included on the device from the factory.

Looking for more computing history? How about a short documentary on the Aiken computers, or a Hack Chat on how to preserve that history?

[Thanks to Stephen for the tip via the Retrocomputing Forum!]

A graphing calculator with a 3D-printed enclosure, with a circuit board next to it

2022 Cyberdeck Contest: The Galdeano Is More Than A Graphing Calculator

September 15, 2022 by Robin Kearey 14 Comments

Graphing calculators have evolved from expensive playthings for rich nerds to everyday tools for high schoolers worldwide. Even though teenagers nowadays carry powerful internet-connected computers in their pockets, math teachers often prefer them to use a clunky Z80-powered calculator in class, if only because their limited performance reduces the potential for distraction. The worst thing a lazy student can do is play a simple game like Snake or Tetris.

But what if you’re not a student anymore and you want a graphing calculator that has up-to-date hardware and infinite customizability in software? Look no further than [Angel Cabello]’s Galdeano, a handheld that has all the features of a modern graphing calculator plus a lot more. The heart of the device is an ESP32, which sits on a custom PCB that also holds a 6×7 array of push-buttons and a 320×240 touch-sensitive color display. It can be powered through a lithium-polymer battery or, like a classic calculator, through four AAA cells. The entire thing is housed in a 3D printed enclosure with color-coded buttons indicating various built-in functions.

The ESP32 runs MicroPython along with a symbolic math engine called Eigenmath. This enables the Galdeano to manipulate expressions, perform integration and differentiation, and plot functions. Porting Eigenmath to a memory-constrained platform like the ESP32 was quite a challenge and required a few workarounds, including a memory partition scheme and even a custom compact font with mathematical symbols.

Thanks to the flexibility of MicroPython and the ESP’s WiFi system, the Galdeano is not limited to implementing a calculator: it can also perform various general-purpose tasks ranging from file editing to controlling a set of smart light bulbs. The project page doesn’t mention any games yet, but we’re sure it won’t take long before someone ports Tetris to this system as well.

Of course, even classroom-grade calculators can be pushed to do much more than their designers intended: they can receive GPS signals, run Debian or even perform ray tracing. If you’re looking for a powerful open-source calculator, this BeagleBoard-based machine runs the R statistical computing environment.

Continue reading “2022 Cyberdeck Contest: The Galdeano Is More Than A Graphing Calculator” →

Coin-Operated Graphing Calculator Console

February 16, 2022 by Chris Lott 8 Comments

Longtime hacker [Peter Jansen] was so impressed with a piece in The Onion from last year that he decided to build this coin-operated Texas Instruments graphing calculator console on a whim (video below the break — warning vertical orientation).

With nothing more to go on than the fake mock-up pictured from the original satirical article, [Peter] was able to scale the dimensions from the photo making a few reasonable assumptions. He built the project over the holidays, enlisting his father and daughter as helpers. The cabinet is framed in 2×3 lumber and faced with wood veneer covered plywood and vinyl overlays for the graphics.

The computing power is from a Raspberry Pi with an Arduino Uno serves as an I/O processor. It was a bit tricky to control a calculator with only two knobs, but he makes it work. However, at 25 cents per plot with no apparent hard-copy capability, this console calculator might be a bit pricey for all but casual plotting over a few beers at the local pub.

You might remember [Peter] from some of his hacks we featured over the years, like his home-brew CT scanner or placing fourth in the first Hackaday Prize contest in 2014 with the open sourced tricorder project.

Continue reading “Coin-Operated Graphing Calculator Console” →

Scientific Calculator Whipped Up In Python

June 2, 2020 by Lewin Day 31 Comments

Scientific calculators were invaluable to most of us through high school and college, freeing us from the yoke of using tables to calculate logarithms and trigonometric functions. Once out in the real world, it’s no longer necessary to use an education board approved device to do your maths – you can do it all on your PC instead. For those keen to do so, [AstusRush]’s latest Python work may be just the ticket!

Far exceeding the capabilities of the usual calculator apps, there’s plenty of useful features under the hood. Particularly exciting is the LaTeX display, which shows equations in textbook-quality human-readable format. There’s also a graphing suite, and capability to handle matricies and vectors. LAN chat is implemented too, useful for working in teams.

It’s a useful tool that may suit better than a full-fat MATLAB install, particularly at the low, low price of free. This is one calculator that CASIO will have to keep their nose out of!

Broken HP-48 Calculator Reborn As Bluetooth Keyboard

August 16, 2019 by Sven Gregori 8 Comments

Considering their hardware specification, graphing calculators surely feel like an anachronism in 2019. There are plenty of apps and other software available for that nowadays, and despite all preaching by our teachers, we actually do carry calculators with us every day. On the other hand, never underestimate the power of muscle memory when using physical knobs and buttons instead of touch screen or mouse input. [epostkastl] combined the best of both worlds and turned his broken HP-48 into a Bluetooth LE keyboard to get the real feel with its emulated counterpart.

Initially implemented as USB device, [epostkastl] opted for a wireless version this time, and connected an nRF52 based Adafruit Feather board to the HP-48’s conveniently exposed button matrix pins. For the software emulation side, he uses the Emu48, an open source HP calculator emulator for Windows and Android. The great thing about Emu84 is that it supports fully customizable mappings of regular keyboard events to the emulated buttons, so you can easily map, say, the cosine button to the [C] key. The rest is straight forward: scanning the button matrix detects button presses, maps them to a key event, and sends it as a BLE HID event to the receiving side running Emu84.

As this turns [epostkastl]’s HP-48 essentially into a regular wireless keyboard in a compact package — albeit with a layout that outshines every QWERTY vs Dvorak debate. It can of course also find alternative use cases, for examples as media center remote control, or a shortcut keyboard. After all, we’ve seen the latter one built as stomp boxes and from finger training devices before, so why not a calculator?

Continue reading “Broken HP-48 Calculator Reborn As Bluetooth Keyboard” →

TI-83 Gets CircuitPython Upgrade

April 4, 2019 by Lewin Day 23 Comments

Graphing calculators are an interesting niche market these days. They’re relatively underpowered, and usually come with cheap, low resolution screens to boot. They remain viable almost solely due to their use in education and the fact that their limited connectivity makes them suitable for use in exams. The market is starting to hot up, though – and TI have recently been doing some interesting work with Python on their TI-83.

Rumor has it that TI have been unable to get Python to run viably directly on the TI-83 Premium CE. This led to the development of the TI-Python peripheral, which plugs into the calculator’s expansion port. This allows users to program in Python, with the TI-Python doing the work and the calculator essentially acting as a thin client. The chip inside is an Atmel SAMD21E18A-U, and is apparently running Adafruit’s CircuitPython platform.

This discovery led to further digging, of course. With some hacking, the TI-Python can instead be replaced with other boards based on Atmel SAMD21 chips. For those of you that aren’t in Atmel’s sales team, that means it’s possible to use things like the Adafruit Trinket M0 and the Arduino Zero instead, when flashed with the appropriate CircuitPython firmware. It’s a tricky business, involving USB IDs and some other hacks, but it’s nothing that can’t be achieved in a few hours or so.

This is a hack in its early days, so it’s currently more about building a platform at this stage rather then building fully-fledged projects just yet. We’re fully expecting to see Twitter clients and multiplayer games hit the TI-83 platform before long, of course. When you’ve done it, chuck us a link on the tip line.

[Thanks to PT for the tip!]

That TRS Jack On Your Graphing Calculator Does More Than You Think

September 25, 2018 by Brian Benchoff 28 Comments

It’s not Apple IIs, and it’s not Raspberry Pis. The most important computing platform for teaching kids programming is the Texas Instruments graphing calculator. These things have been around in one form or another for almost three decades, and for a lot of budding hackers out there, this was the first computer they owned and had complete access to.

As hacking graphing calculators is a favorite for Maker Faires, we were pleased to see Cemetech make it out to this year’s World Maker Faire in New York last weekend. They’re the main driving force behind turning these pocket computers with truly terrible displays into usable computing platforms.

As you would expect from any booth, Cemetech brought out the goods demonstrating exactly what a graphing calculator can do. The most impressive, at least from a soldering standpoint, is their LED cube controlled by a graphing calculator. The electronics are simple, and just a few 595s and transistors, but this LED cube is taking serial data directly from the link cable on a graphing calculator. Of course, the PCB for the LED cube is designed as an Arduino shield for ease of prototyping, but make no mistake: this is an LED cube controlled by a calculator.

If you can send serial data to a shift register from a graphing calculator, that means you can send serial data to anything, bringing us to Cemetech’s next great build featured this year. It’s an N-gauge model train, with complete control over the locomotive.

There’s a lot more to controlling model trains these days than simply connecting a big ‘ol variac to the tracks. This setup uses Direct Cab Control (DCC), a system that modulates commands for locomotives while still providing 12-15V to the tracks. There’s a good Arduino library, and when you have that, you can easily port it to a graphing calculator.

Cemetech is one of the perennial favorites at Maker Faire, and over the years we’ve seen everything from the Ultimate TI-83+ sporting an RGB backlight and a PS/2 port to a game of graphing calculator Whac-A-Mole. It’s all a great example of what you can do with the programmable computer every 90s kid had, and an introduction to computer programming education, something Cemetech is really pushing out there with some hard work.