Conways’ Wall Of Life And Whiteboard Emporium

January 27, 2011 by 6 Comments

White board beats chalk board, LED marquee beats white board, and an LED white board trumps them all.

This hybrid lets you draw on the surface with dry erase markers while Conway’s game of life plays out underneath. [Bert] sent us this tip after seeing yesterday’s office marquee. This version is quite similar in appearance but the guts are very different. Inside you’ll find a Parallax SX28 microcontroller doing the heavy lifting. The display is multiplexed but they didn’t go with a common 595 shift register, but a beefier MAX6979 LED driver. We’re not too familiar with this part but it does have a lot of nice features like constant current, and automatic shutdown if serial data stalls for more than 1 second. This is a low-side driver so transistors are used to connect voltage to the rows; the opposite from the setup we looked at yesterday. This was built several years ago and is still working happily even though its permanent home is a breadboard. Source code can be found on this page.

Falling Sand Game On An FPGA

December 15, 2010 by 17 Comments

This falling sand game runs on a field-programmable gate array. The Altera Cyclone II resides at the heart of that development board, running the game which was written in Verilog. [Skyler Schneider] modeled his project after a Java version of the game called Pyro Sand Game. He treats each pixel of the 640×480 VGA screen as its own cell, following a set of rules to change the cells around it. This is very similar to Conway’s Game of Life, except that there are different categories of cells that behave uniquely (oil, water, plant, fire, etc.) and gravity is a key factor. Of particular interest to us were the rules for each cell, and the method [Skyler] used to feed and sync the VGA output. After the break you can see his demonstration videos, which walk through all of the features including the Troll button.

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Reboot Life In A Heartbeat

February 18, 2010 by 18 Comments

This hoodie senses your heartbeat and uses it to control Life. Conway’s Game of Life, popular in all kinds of electronics projects, uses a grid of cells coupled with a set of rules to mimic the life and death of simple organisms. This iteration displays the game over your own heart, then taps into your heart rate, resetting the game at the beginning of each cardiac cycle. We guess you could say that Life goes on only if you do not.

The EKG circuit that detects the heartbeat is made up of an IR transmitter shining through the tip of your finger to a receiver. An ATmega168 running the Arduino bootloader controls the EKG circuit and resets an ATmega48 which is responsible for Life. [Joe] admits that this is overkill but he’s currently without an AVR programmer; he went this route to make it work. The stylishly-geeky hoodie is taken for a test run (er… test-hop?) after the break.

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Capacitive Buttons Control All Life

September 28, 2009 by 7 Comments

capacitive_game_of_life

Projects involving Conway’s Game of Life and utilizing a Nokia 3310 screen are quite popular with electronics hobbyists. [Droky] put these two together and went one step further by adding capacitive sensors to control the Game of Life. His work is a great example of how to use the Atmel QTouch capacitive sensor (QT100a datasheet). This chip does the heavy lifting that we’ve seen in other touch sensitive solutions. It operates from 2V-5.5V, requires only three capacitors and a resistor, has a one pin active high output, and sells for around $1 in low quantities. One thing [Droky] overlooked in his board layout is the ground pad on the bottom of the WSON6 chip. He was able to make it work by masking the trace that runs under the chip but you will want to alter the layout in your own designs.

If you’ve used the QT100a before we’d like to hear about your experience, and find out if button debounce handling is necessary with this chip. Let us know in the comments. You can see a video of it in action after the break.

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LED Life And Charlieplexing

October 24, 2008 by 7 Comments


Yesterday, we featured [Andrew]’s orientation aware camera. We want to highlight another one of his projects: LED Life. It’s a 6×5 LED matrix playing Conway’s Game of Life. He used the low power MSP430 like our e-paper clock. The best part of the writeup is his explanation of how Charlieplexing works. Microcontroller GPIO pins generally have three possible states: output high, output low, and input. This combined with the directional nature LEDs and some creative wiring means you can run a large matrix of individually addressable LEDs with just a few IO pins. Instead of just flipping the IO pins on and off you change their assigned state. Have a look at [Andrew]’s site for some great illustrations of how the system works. A video of his LED Life board is embedded below. Continue reading “LED Life And Charlieplexing” →

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Hackaday Links: June 30, 2024

June 30, 2024 by 14 Comments

A couple of weeks back we featured a story (third item) about a chunk of space jetsam that tried to peacefully return to Earth, only to find a Florida family’s roof rudely in the way. The 700-gram cylinder of Inconel was all that was left of a 2,360-kg battery pack that was tossed overboard from the ISS back in 2021, the rest presumably turning into air pollution just as NASA had planned. But the surviving bit was a “Golden BB” that managed to slam through the roof and do a fair amount of damage. At the time it happened, the Otero family was just looking for NASA to cover the cost of repairs, but now they’re looking for a little more consideration. A lawsuit filed by their attorney seeks $80,000 to cover the cost of repairs as well as compensation for the “stress and impact” of the event. This also seems to be about setting a precedent, since the Space Liability Convention, an agreement to which the USA is party, would require the space agency to cover damages if the debris had done damage in another country. The Oteros think the SLC should apply to US properties as well, and while we can see their point, we’d advise them not to hold their breath. We suppose something like this had to happen eventually, and somehow we’re not surprised to see “Florida Man” in the headlines.

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Old Casio Calculator Learns New Tricks

April 6, 2022 by 12 Comments

[George Stagg] recently found himself stung by the burden of free time while in lockdown. Needing a project to keep him occupied, he decided to upgrade his 90s Casio CFX-9850G calculator to run custom machine code.

All [George] really wanted was for his vintage calculator to understand Reverse Polish Notation (RPN). The calculator in question can already run its own version of BASIC, however the bespoke Hitachi CPU struggles performance-wise with complex programs, and wouldn’t be a realistic way of using RPN on the calculator. An RPN interpreter written in assembly language would be much faster.

The first step in cracking this calculator wide open was a ROM dump, followed by writing a disassembler. Incredibly, the MAME framework already featured a ‘partial implementation’ of the calculator’s CPU, which was a much needed shot in the arm when it came time to write a full-featured emulator.

With the entire calculator emulated in software, the plan from here involved replacing one of the BASIC commands in ROM with new code that would jump to an address in RAM. With 32KB of RAM there ended up being plenty of room for experimentation, and uploading a program into RAM was simplified by using Casio’s original backup software to dump the RAM onto a PC. Here, the contents of RAM could be easily modified with custom code, then uploaded back into the calculator.

With RAM to burn, new routines were created to write custom characters to the screen, and a new font was created to squeeze more characters onto the display than normal. [George] ended up porting a Forth interpreter, which defaults to RPN style, to finally achieve his humble objective. He also managed to get a version of Conway’s Game Of Life running, check out the video after the break.

We can’t get enough of our calculator hacks here, so make sure to check out the CPU transplant on this vintage Soviet calculator.

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