We’re sure there are more expensive LED controllers out there, but the TI-84 has got to be up there. Unless you have one on hand, then it’s free. And then you’ll doubtless need an SPI library for the famously moddable graphing calculator.
[Ivoah] is using his library, written in assembly for the Z80 processor inside the TI, to control a small strip of DotStar LEDs from Adafruit. The top board in the photograph is an ESP8266 board that just happened to be on the breadboard. The lower Arduino is being used as a 5V power supply, relegated to such duties in the face of such a superior computing device.
Many of us entertained ourselves through boring classes by exploring the features of TI BASIC, but this is certainly a step above. You can see his code here on his GitHub.
After his proof-of-concept, [Ivoah] also made a video of it working and began to program a graphical interface for controlling the LEDs. Video after the break.
Seems like potentially a really affordable basis to introduce students to some programming in a school that has or has students who have graphing calculators, give them simple little projects and have them do the control via their calculator.
Indeed! Cemetech is a great resource for anyone wanting to get into calculator programming, wether for educational purposes or just plain fun. Christopher Mitchel (the site’s founder) even wrote a book which goes in-depth about programming graphing calculators. https://www.manning.com/books/programming-the-ti-83-plus-ti-84-plus
Fat fingered the “Report Comment” link. Please ignore.
Only problem is that those calculators are a little pricey for what you get.
They are a bit pricey, but I bought one at second hand store for $1, and the Remedial Math department of the college I attended gave me 2 or 3 that had weak/failed displays.
Oops! I was thinking of the TI-83+ not the Ti-84!
TI graphing calculators have ways to write programs built right into the OS. TI-83 BASIC was my first language. My first program was an animation of a stick man shooting another stick man in the face.
~memories~
Nice to see this one finally arrive. But what happened? It arrived via my subscription to the WordPress service at 3:44AM this morning. But it says it was posted at 7PM yesterday. Incidentally Ivoah, I’ve reviewed your code inside Git, and it is an interesting project.
Update: The comment subscription robot does include a date of yesterday in its message for what we see here.
I only have a ti nspire cas that without this link connector, no luck.
The Nspire series is capable of much more than this, for example: running full blown Debian https://hackaday.com/2014/11/18/running-debian-on-a-graphing-calculator/ (also one of my projects)
Wow! More than I can expect!