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Welcome to Cemetech! Since 2000, Cemetech (pronounced KE'me'tek) has been teaching programming and electronics and developing software and hardware. Among Cemetech's specialties are TI, HP, and Casio graphing calculators like the TI-84 Plus, TI-Nspire, HP Prime, and Casio Prizm, embedded and DIY electronics, and computer and web programming. Cemetech provides a safe, friendly space for people to learn, show off projects, and share knowledge and expertise. Our staff of friendly volunteers hang out on our forum and IRC and SAX chatrooms, and are happy to help.
Cemetech Going to World Maker Faire 2016 for 5th Year
Published by KermMartian on September 26, 2016 at 12:17:41 PM CST | Discuss this article (7)

For the past four years (2012 recap, 2013 recap, 2014 recap, 2015 recap), Cemetech has been showing off programming and hardware hacking with graphing calculators at World Maker Faire in New York City. This September, we'll be reprising our role once more, presenting our latest programming instruction and hardware hacks at World Maker Faire 2016. Held in Flushing Meadow Park next to the New York Hall of Science the weekend of October 1st and 2nd, the Faire will hold the latest and greatest in DIY hacking. This will be the Faire's seventh year, and each year that we've attended, it has grown in popularity, attendance, and most importantly, the quality and variety of projects displayed. We have been brainstorming our plans for the Faire, and our team has begun building the various displays we'll need for the occasion. We hope you'll come visit our booth if you're in New York at the beginning of October, and with less than a week left until the Faire, we have our work cut out for us to complete our preparations.

Among the many things we plan to display this year at Maker Faire:
  • GPS demo: A hacked-up version of the GPS for graphing calculators project.
  • Game Boy camera demo: The Gameboy camera + TI-84 Plus C Silver Edition project, properly calibrated for sunlight.
  • Whack-a-Mole: Built with a TI-84 Plus C Silver Edition, a TI MSP432 Launchpad, and lots of RGB LEDs and light sensors, the Whack-a-Mole project was a hit at World Maker Faire 2015 and T^3 2016.
  • Learn to Program demo: A giant calculator emulator, with key entry from a real TI-84 Plus C Silver Edition calculator. Aims to teach visitors to write a simple guessing game in 60 seconds.
  • Simplified networking demo: four TI-83 Plus calculators connected via CALCnet, running the Flourish demo.
  • Interactive calculators for games: a TI-84 Plus CE, TI-84 Plus C Silver Edition, TI-84 Plus Silver Edition, and if any of them are still working, a Casio Prizm, with games and other programs loaded.
  • Sound demo: A TI-84 Plus Silver Edition with mobileTunes and songs by Alec "qazz42" Szigeti and Thomas "elfprince13" Dickerson, plus my floppy drive music with a TI-83 Plus project.
  • Calculator ECG: An ECG built with an Arduino and a TI-84 Plus C Silver Edition, and if time permits, the TI-Innovator Hub.

We look forward to seeing you at the Faire, or if you can't make it this year, to bringing you updates here on Cemetech, on our Twitter feed, and on our Facebook page.

More Information
General World Maker Faire 2016 information

A selection of photos from our booth in 2015.

Hands-On with the TI-Innovator
Published by merthsoft on September 20, 2016 at 7:27:36 PM CST | Discuss this article (5)

Last week I found a TI-Innovatorô Bundle for sale and figured I'd pick it up to play with it. I wanted to post my thoughts on this device as a programmer, and as a TI calculator enthusiast. If you're not familiar with the TI-Innovator, it's a box containing a TI MSP432 Launchpad development board, loaded with a custom firmware, that you can connect to your calculator. The upshot is that it's an educator-friendly way to teach students about coding and electronics, something of a more formal version of our popular ArTICL library to explore electronics projects with Arduinos and TI calculators. It consists of the TI-Innovator hub itself, connected to your TI-84 Plus CE or TI-Nspire CX calculator, and can be expanded with two accessory kits from TI. The I/O Module Pack contains a servo, vibration motor, light sensor, and white LED for TI's "Science Through Engineering Design" activities, while the Breadboard Pack contains discrete electronic components and a breadboard for the Path to STEM Projects activities.

I will say, right out of the box, it's a very nice looking device. It's fairly a fairly straight-forward process to get started with. I updated the software on my CE, installed the app, plugged it in, and wrote a quick blinking program:
Wait 1
Wait 1

And, viola, a blinking light!

I will say, right out of the box, this is a joy to program. One of the things I love about programming calcs is the ease of getting in to it. There's a simple menu interface so you don't need to remember every keyword, and it's easy to just explore and make something happen. This holds true for the Innovator Hub, as well. I knew right away that this would be a great way to get kids to play with electronics and learn how to program.

After the blinking light, I wanted to do something a little more complex. I had a lot of things I could play with with the bundle, but wanted to keep it just using the Hub for now. So, the next thing I figured I'd do was make some sound. This is where I ran into my first error, and boy does the hub let you know something went wrong:

The problem was I was doing Send("SET SOUND F to try to send a sound of frequency F. This doesn't work--it doesn't know about the variables on the calculator. This was fixed with Send("SET SOUND eval(F. And I had a chromatic scale playing:
Send("SET SOUND eval(F

Again, I found this great fun. I noticed when playing the music, that the RBG LED was blinking, and then made a little program to cycle between the lights. At first I thought there would be many colors, but I think that each can only be on or off. This is where I learned that you can use 0 for off and 1 for on. This makes programming a little easier when you're doing on and off programmatically. I don't have a video of that, because it's not terribly exciting. Note: I have since learned from this page that you can do more with the on-board RGB LED. The lesson here: Always read docs.

However, this made me want to play with the RGB LED that comes with the breadboard kit. This reminded me why I didn't pursue electronics any further in my studies: I dislike dealing with and hooking up all these components. I got it all hooked up, but will admit that I couldn't figure out how to program it. It would be nice if the instructions booklet had more details on how to do things. That said, I decided instead to make a counter using the seven segment display.

The display that comes with the bundle is an LTS-4301JR. I looked up the datasheet to hook it up, and again couldn't figure out the code. That's when I found this page which has lots of useful information for hooking up these kits, and I got it working.

At this point I had had enough with electronics components and breadboards, so I figured I'd play with some of the other kits that came in the bundle. The range finder seemed like it would be fun, so I made a little program that translated range to frequency, and made a little fake Theremin:

Overall, I have to say I'm quite impressed with this. Out of the box, with just the hub, you can do some pretty fun things. I wish the Hub itself had some built-in inputs--maybe the buttons on the board can be read from the calc if you take off the cover. I'd like to experiment more with the built-in stuff. There are some buttons and some jumpers.

Having simple inputs and outputs is really nice for getting people up and running with some fund things right away, and having the more complicated breadboard stuff makes it so you can basically do anything with the calculator driving. I think this is a great way to get kids into programming, and I look forward to seeing what teachers and TI do with it in the future! If you have any questions about using the TI-Innovator or want us to try some experiments with ours, please don't hesitate to ask.

Projects of the Month: August 2016
Published by tifreak8x on September 4, 2016 at 12:57:04 PM CST | Discuss this article (2)

Hey there Cemetechians! How's it going? Seems things have picked up slightly this past month with projects getting worked on, and hopefully I didn't miss out on reporting on anyone's works of art!
  • TerraCalc: TerraCalc aims to be a Terraria clone, which is a 2D action-adventure sandbox. Dankcalculatorbro is currently programming this project, and has shared some screenshots of the first feature, generating terrain. At latest, he's rewriting code to be more efficient and optimized.
  • Video 84+ converter: Iambian resurrected an old project of his, bringing it back into the limelight. It converts a video file into an App that plays the video, and actually looks really good on the monochrome (TI-84 Plus family) calculators. Take a look at the topic, check out the video that Iambian shot of his calculator playing a YouTube video, and let him know what you think!
  • Sorcery of Uvutu: After just over 3 months, 123outerme has come out of hiding and posted up a small update regarding this game, stating that a new world has been created, along with changes to the save file. He has also sent his beta testers a new closed beta version, which should push progress along as well. Check the post out for a screenshot and more information.
  • Atomas 84+CE: This game is a puzzle type where you are given atoms and you combine them to create new elements for the goal of getting an element of the highest atomic number. It's an accurate port of a very popular smartphone game, and just as addictive as the original. Check out the thread for some impressive screenshots, a download link, and a whole lot more information!
  • Tourn II: Tourn II is a fighting-style game by 123outerme. It is similar to the old Mortal Kombat games for the SNES, uses actual sprites, and will have a variety of combos and levels. Check out the thread to see his screenshots showcasing the start of his work!
  • Pokemon Plus: Before you get too excited, this isn't a Pokemon game. This is more of a Pokedex and assistant for Pokemon Go players to determine statistics, evolution chains, and more for Pokemon that they catch. This project is for the Casio Prizm and looks absolutely fantastic, closely mirroring the calculator's own UI. Check the thread for more information, including a download link!
  • Endless RPG: Battlesquid has been hard at work this past month making massive progress on his role playing game for the TI-83 Plus/TI-84 Plus family. This includes massive optimizing, hex code additions, and bug fixes.
  • ICE Compiler: ICE has been seeing a lot of work this past month, adding quite a number of features to the already long list that it was toting before. Go check out PT_'s work in the thread and read up on all of his hard work. In particular, PT_ encourages ICE's users to make and publish some new projects in the language to help motivate more programmers to try it.
  • TI-84+CE Programming Tutorials: A long-running collaboration between MateoConLechuga and Adriweb to teach people how to program in C and ez80 ASM for their TI-84 Plus CEs. Check out the topic (which links to the tutorial site) and let them know what you think of their progress!
  • ConvTile: Another in the long line of tools MateoConLechuga has released for TI-84 Plus CE programming and development, this particular tool takes the file generated from Tiled and makes it usable to create tilemaps for your projects on the TI-84 Plus CE. If this sounds like something useful to you, make sure to check this tool out and let Mateo know what you think about it!
  • C SDK and libraries: MateoConLechuga has released an update for the C SDK that fixes numerous bugs and adds some neat features. Check the topic and make sure you update if you program your CE in C!

Hopefully as our members return to school and have time for programming more, we'll see this list of ours get longer once again. We look forward to what you, our members, put on to the calculator next! Until next month!

OS 5.2 for the TI-84 Plus CE: New TI-BASIC Commands
Published by KermMartian on August 31, 2016 at 10:02:33 PM CST | Discuss this article (34)

This week, TI released the newest operating system for the TI-84 Plus CE, TI-84 Plus CE-T, and TI-83 Premium CE: OS 5.2. This updates brings major useful updates for TI-BASIC programmer, as well as a few improvements for regular users. We want to discuss some of the most important updates, outside of small bugfixes. First, some commands and tokens:
  • They updated some BASIC commands to interact with the TI-Innovator, released last month. Sending (Send() and receiving (Get() strings is now possible, and deep inside, there is now extensive code to communicate with serial-over-USB devices, including the TI MSP432 Launchpad and the Arduino family of microcontroller boards.
  • eval( - basically the same as expr(, but it stores the answer in a string, which is often necessary by BASIC programmers, who needs this token in a program. Instead of the large and slow LinReg routine, use this token to simple convert a calculation to a string. This was added to make it easier to construct commands to send to the TI-Innovator.
  • toString( - this token is pretty similar to eval(. There is one big difference however: toString( handles the format in which the result was returned. expr( and eval( cannot handle lists as output, while toString( handles lists, matrices and more. This is one of the most-missed tokens in BASIC ever, so it's a good thing TI added it!
  • Wait - pauses the program execution for a specific amount of seconds. Instead of using something like rand(999 or a For-loop, just use this, if you want to have a delay in your program, for example when displaying text, and let the user read it.
  • There are also a variety of new tokens that have numerical values (like the color tokens, eg RED, BLACK, BLUE, etc.) for working with the TI-Innovator, like LEFT (0), CENTER (1), and RIGHT (2).
  • There is a new pieceWise( command in the OS, but it doesn't appear to be useable yet.
There are also various functionality updates:
  • This update is rather useful in combination with an online BASIC program editor, such as SourceCoder. When your program has an error somewhere, you don't need to figure out at which line it is, because the line number of the error is shown inside the status bar! Could be useful for debugging.
  • There is a big focus on sequences. Outside of adding 15 tokens relating to sequences, they added support for u(n)=u(n-1)+u(n-2) for example. It can now take the 2 previous results, instead of only the last one. Because it's possible, let's just display the Fibonacci Sequence, shown below.
  • The calculator has some improvements when hitting [ALPHA]+[one of the top 5 keys]. It adds in blue font how it will look like at the homescreen in Mathprint-mode.
  • TI added some tokens which are all probability-related. invNorm( now can take another argument, LEFT, RIGHT or CENTER, for the area under the curve. It should be a bit easier when using invNorm(
  • A new application is published, called Hub. This small app adds a menu to the program editor, which all the sending/getting commands in it.
  • Many TI apps got an upgrade, so if you use one of them, be sure to download the latest version!
  • The exam mode changed a little bit, program won't be erased, so when going back to normal mode, you will still find it on your calculator.
  • Outside of all the calculator changes, there is also a new version of TI Connect CE, also labeled version 5.2.

We hope you enjoy this update, and highly recommend to change your programs, using the newest BASIC tokens, which are really useful. We particular look forward to testing out the new TI-BASIC programming features with the TI-Innovator. Special thanks to Cemetech moderator PT_ for researching and writing most of this article!

TI-84 Plus CE OS 5.2