Lego Mindstorms Calculator




This calculator uses a modified version of one of the Mindstorms tutorial's code to add how many times you press one touch sensor to how many times you press another touch sensor. To subtract, you have to add negative numbers.

Oh and sorry for the poor picture quality, I took everything on an iPhone camera :P

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Step 1: Parts

Two touch sensors
8 black pegs
2 "L" bars
Mindstorms NXT brick
2 connector cords for sensors

Step 2: Add the L Bars

Attach the L bars to the NXT with the little peg things.

Step 3: Add the Sensors

Attach the sensors to the L bars with the leftover peg things.

Step 4: Plug the Sensors Into the NXT

Plug the left sensor into port 1 and the right sensor into port 2. I put two longer pegs in the NXT to keep the wires in place, but it won't affect anything if you leave them out.

Step 5: Download Code

Download the 2 files on this page and sync "add.rbt" to your NXT brick. 

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    8 Discussions


    Reply 4 years ago

    I honestly have no clue where the original file went and don't have the NXT software to reconstruct it after going through a couple laptops since using it, sorry. From what I am recall, though, it was a pretty simple thing with one touch sensor incrementing a variable and the other decrementing, but I don't remember how I switched from first to second number or added them afterwards. Might have been something like posting both sensors simultaneously or something? If you feel like getting something working off that and post it, I'll update crediting you.


    Reply 4 years ago

    I searched a bit on the lego forums and found some other calculator programs. Most of them were built in the way you described them.
    I can understand why you don't have the file anymore, this was posted a long time ago, lol. It's a bit weird because googling NXT calculator brings up your instructable as one of the top 5 answers.
    For anyone stumbling upon this, here is a link to the lego forums calculators:

    Anyways, thanks for helping me out.

    Lego man 201

    8 years ago on Introduction

    Dude im getting the computer soon probaly gonna make a whole bunch of things