Hi!

I am not a lurker, I found you this evening after a rabbit-trail extending from a brief shot of a TI-91+ on a Youtube video - it reminded me of an old HP BASIC computer thing (one line LCD, probably made in 1986 or so) and I got nostalgic enough... then found out about the CBL2 and... here I am!

I have an 84 from my undergrad days, can't recall + or CE or whatnot. Many years ago I coded in GW BASIC, QBASIC, and QB45 - then I did very limited tinkering with C++, and whatever it is that's used in Marlin on the Arduino IDE (it seems C-ish, but not ++ ).

I would like to make a TI-91+ do things in the shop - aside from being an awesome calc, I'd like to make it maybe send instructions to a Mega-2560 clone board, that would then drive some stepper motors? Perhaps make use of the CBL2 for things in the lab? Combine these two such that some TTL pulses would then cause a stepper to step?

Can TiBasic be coaxed to send GCODE over it's I/O port?

Maybe.... draw a parametric curve?

Anyhow, you guys seem as friendly as the people at Hobby Machinist (where I also write oddly) - and that is weird for me because, well, coders tend to have..... somewhat abrasive manners in dealing with the "wet-ware" (humans).

I hope to make some digital friends, and maybe my decades gone obsession with coding will come back.

Oh - I also have an R-Pi that really needs to be a Tricorder some day...

Hi there MerlincMan - glad you found us.

You mention the TI-91+, which doesn't correspond to any released model that I'm aware of? However there is the TI-92+ if that's what you have?

Unfortunately I am not very familiar with 68K BASIC for that calculator, though there are people here who may be able to help out.

Yep! You'll probably want this Arduino library to get your Arduino talking to your TI calculator, then you can implement something on the Arduino side to get bytes from a RS232 port to the calculator's I/O port. Normally, you'd be able to use something like a TI Graylink link cable, but most G-Code machines I've touched expect something other than 9600 8-N-1 encodings; the Arduino solution allows for changing the serial port settings in software.


It's a versatile and surprisingly inexpensive device, but I/O using the CBL2 command set is pretty sluggish; you wouldn't be able to do a control loop or anything at cutting feedrates. I've done some experimenting with CBL2 digital I/O in the past. If you do feel like playing around with the CBL2 (it's nice having sensor inputs on the calculator), the Vernier LabPro is just a better device all-around and costs only a little bit more; it has better resolution and much more I/O, while being fully backward-compatible with the CBL2.