Questions about programming the various LEGO programmable bricks, including Mindstorms (EV3, NXT, and RCX), Wedo and Scout, in either the provided languages and editors, or more advanced languages.

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1answer
53 views

Direct/system command for reading the display buffer of EV3 bricks?

I recall being able to read in the display buffer of NXT 2.0 bricks over Bluetooth/USB by issuing Read IO Map system commands. I've looked through the bytecodes and communication documentation for the ...
4
votes
3answers
190 views

How can EV3 Gyro sensor drift be handled?

EV3 robots can use a Gyro sensor to determine the direction the robot is heading. The initial conditions are important. The sensor needs to be still and then the sensor reset. However, once in a ...
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0answers
31 views

Sense and Display blocks

I put move forward until it sees the red color then it stops and it writes red color But the teacher told us there is problem so where is the problem?
2
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1answer
135 views

Sort the program list on EV3

When uploading a project to the EV3 brick, is there a way to control the sorting order of the programs on the brick? E.g: Prog_1 Prog_2 Prog_3 ... When playing a robot match in FLL one often needs ...
4
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1answer
43 views

DNX on Lego Mindstorms

I am not familiar with ARM development but I am wondering would it be possible to compile DNX against Lego Mindstorms EV3 processor. I know there is some ARM support and even there are some builds ...
1
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1answer
77 views

Site or example project / downloadable programme resource anywhere for the EV3 mindstorm?

There seems to be lots of available examples for the NXC version, but I can't find anything for the EV3. I thought that there would be a load of example project files with the software but there's ...
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0answers
43 views

Is there any way to find misplaced bricks in LEGO NXT Programming?

I am working on a Mindstorms NXT project. Due to annoying bug (cannot find terminal hotpoint thingy) I can't delete a specific block, and if I do so, part of the program will be cut off from the main ...
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0answers
30 views

EV3 Programme won't load to brick

I have installed EV3 on my PC and am trying to load a program into an NXT 1 Brick. When I click the down load button on the EV3 screen the Brick beeps twice and the program does not load. What am I ...
6
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2answers
125 views

Making an ATM with an EV3

I am building an ATM using my LEGO Mindstorms EV3, but I ran across a problem. The problem is that I want to be able to input the amount of money that I want to get out of the ATM but I can only have ...
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2answers
91 views

Which program do I use to program my rcx 1.0 or 1.5

I am getting an RCX and I know it is ether a 1.0 or a 1.5. Which program do I use to program my RCX?
2
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1answer
195 views

EV3 turning in circles

New programmer feeling my way around. I set the most simple "steering block" to 25, the power to 50, and the number of motor rotations to 40 or 50. Then I let it run expecting the bot to go in a ...
3
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1answer
105 views

Where can I learn how to program an NXT using C#?

I've been toying around with my NXT 2.0 set for a few years now and I would like to learn how to program it using C# language. I have no experience in coding and I am definitely not a computer geek. ...
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3answers
926 views

The Mindstorms EV3 Software crashes on OS X Yosemite 10.10.3. What do I do?

It's crashing on startup which is really irritating. When debugged with terminal it says this: Unhandled Exception: System.UnauthorizedAccessException: Access to the path is denied. [ERROR] FATAL ...
2
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1answer
76 views

Absolute Turning Motor in NXC

How can I turn my motor to 123 degrees, not for 123 degrees? I tried the PosRegSetAngle("output", "angle") command and didn't work. Documentation for PosRegSetAngle
2
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2answers
132 views

Access WeDo on OS X from a real programming language

I'm trying to talk to the WeDo USB interface from Python or really any real programming language. I tried the clever WeDoMore library, but can't get it to bind the WeDo. I think this is because the ...
4
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1answer
201 views

Custom EV3 Block: “Unable to compile…” (“string subsection”)

I am attempting to make a custom block according to the EV3 Block Developer kit (found here). I was able to create a simple block that returns the length of a string. This is what it looks like: (The ...
3
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2answers
217 views

Have Multiple Inputs to Programming Block

Originally, I had a simple program to move until the robot hit a wall, then it reversed and turned and moved again, repeated to infinity. It works by turning the motors on, waiting for input from the ...
2
votes
1answer
141 views

Tufts MAZE LabView Program Will Not Run on EV3

Through the 2012 LabVIEW for LEGO software package, I found an example of a maze from Tufts. I cannot get it to run on an EV3. It appears to just constantly execute the initialization. How can I ...
1
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1answer
163 views

Raw RGB data to Color?

I'm trying to convert the raw RGB values from a Colour Sensor into HSL but it doesn't seem to be working: R = rgbn[INPUT_RED]; G = rgbn[INPUT_GREEN]; B = rgbn[INPUT_BLUE]; var_R = ( R/255 ); var_G = ...
2
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3answers
826 views

Programming NXT color sensor with NXC?

Currently I am working Lego robot that solves 2x2x2 Rubik's cube. I am programming Lego Mindstorms NXT 2.0 color sensor in BricxCC. I already have RGB data with the command ReadSensorColorRaw. I ...
6
votes
1answer
745 views

How can I rotate an EV3 motor an exact number of degrees using RobotC?

I'm trying to rotate the motor of an EV3 by an angle of 50°. I can't. How I can rotate a NXT/EV3 motor by a given angle using RobotC?
2
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0answers
64 views

Programming the LEGO Mindstorms T-Rex [duplicate]

I followed the instructions up to the MoveAbsolute My Block for the T-rex but I'm not able to link the last connection (Brake at End). Can anyone advise what I might need to change?
2
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2answers
106 views

I need a block that can combine a movement program with NXTbee radio

I am a student. I am working on a science project using LEGO Mindstorms robots enhanced with NXTbees creating a mesh network. My engineering mentor has me using LabVIEW. I am trying to find a block ...
2
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0answers
184 views

Daisy chaining EV3 with RobotC

I'm trying to run EV3 programs with RobotC and trying run on EV3 Daisy Chaining. I have three independent EV3 bricks labelled A,B,C. I want, according to the color reading by the color sensor on ...
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0answers
74 views

Use of Mindsensors IMU with Labview

I thought someone could help me with a the Mindsensors AbsoluteIMU ACG and its use with the Lego Mindstorms NXT. Is it possible to use it with and get data out of it?
3
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1answer
138 views

Execute program programmatically

I want to program our Ev3 for FLL (class assignment), and I want to use an object oriented approach in a very procedural environment. Is there a programmatic way to execute another program inside the ...
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3answers
317 views

Reading current motor speed, opOutput_Read

I'm trying to read current motor speed using direct command: Instruction opOutput_Read (LAYER, NO, *SPEED, *TACHO) Opcode 0xA8 Arguments (Data8) LAYER – Specify chain ...
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0answers
68 views

After adding a MyBlock icon to the EV3 palette of MyBlock icons, how can the new icon be associated to an existing MyBlock?

After following the advice given in adding a MyBlock icon to the EV3 palette, can the icon be associated to an existing MyBlock? Something better than copy/paste the contents of the existing MyBlock ...
3
votes
1answer
362 views

How to program light sensor to follow moving light using NXT

Cannot figure out how to simply program Lego Mindstorm NXT robot to follow another moving robot that has a bright LED light attached to it. Currently my programme looks like this:
2
votes
1answer
310 views

Trying to get a modified traffic signal challenge worked out

The challenge is for a robot to go around the perimeter of a rectangular field and execute 90 degree turns when it gets within 4.5 inches of a wall. Simultaneously, if the bot encounters a red flag, ...
2
votes
2answers
177 views

Lego EV3 - Get output device type, opOUTPUT_GET_TYPE

I would like to know what kind of motor (XL, L) is connected to EV3 output port (A|B|C|D). I need to use direct command: Instruction opOutput_Get_Type (LAYER, NO, *TYPE) Opcode ...
5
votes
1answer
202 views

EV3 RMIregulatedMotor Regulation Problems

I have problem with regulation of the motor when I control EV3 with Bluetooth. Here is the code: RemoteEV3 ev3 = new RemoteEV3("10.0.1.1"); ev3.setDefault(); RMIRegulatedMotor leftMotor = ...
3
votes
1answer
60 views

NXT brick not executing programs correctly

I have an issue that I am hoping someone might be able to resolve: We're using Mindstorms in the classroom as part of a STEM program and have one NXT brick that wont execute programs correctly. The ...
5
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2answers
2k views

Is it possible to edit a my block input parameter value?

I have created my blocks but want to change the input parameter to a negative. Is this possible or must all the myblocks be re-written?
2
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1answer
127 views

How make robot turning going straight?

I have been struggling with this function for a while. I want my robot to turn left until it detects black then turn right until it hits black again. Then, I will divide the angle in half and call ...
3
votes
1answer
110 views

Teleoperated arm trouble

I have built a robotic arm with the lego Mindstorms ev3. My goal is to control its motion via teleoperation, that is , to have a gyro sensor strapped onto my arm and have the robot mimick the up and ...
2
votes
1answer
63 views

How to make NXT bricks communicate information?

Is it possible to connect, in some way, two NXT bricks that has program functions running on both. For example, Brick one would tell brick two that it is okay to start a program. Are there any sensors ...
4
votes
2answers
79 views

Is there a time mechanism that can be added to an NXT program?

I wanted to create a system where an NXT block would be set into function at a certain time of day (maybe 5:00 and then 5:10 and so on). I would want the timing function to be embedded into the NXT ...
5
votes
1answer
455 views

How to build an automatic Lego train system?

I was wondering if anybody has ever tried using the IRLink NXT sensor to make an automated train system and if so, what kind of setup did you have to make it all work? I have been working on a train ...
1
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2answers
2k views

EV3 parallel MyBlocks, but only one working

TL;DR = Is there any obvious reason why a MyBlock, added twice in parallel to a program, will only run one of them? In my EV3-G program, I have a MyBlock which uses the Proximity Heading to control ...
6
votes
1answer
471 views

Pass sensor or motor port number as a parameter

I want to create a block for one light sensor or one motor separately. Is it possible to give the number of the port as a parameter to a sensor or motor block via data wire? In NXT-G it was possible.
3
votes
2answers
705 views

IDE recommendations for EV3 programming

Does anybody have any recommendations for non-GUI programming of the EV3 unit? I'm impressed by the LabVIEW software, but as a professional C# and VB.Net programmer (with C, C++ experience), I find ...
4
votes
1answer
573 views

can't send multiple commands to EV3 using Python

I want to use Python to send commands to an EV3 brick. In C++ things work as expected - for instance, this starts the motor on port A and then stops it after a while: #include <unistd.h> ...
5
votes
3answers
641 views

Is there a microphone that works with Mindstorms EV3?

I'm planning to program my EV3 robot to do voice chat over VOIP using ev3dev and a Debian program. Is this possible? Are there microphones known to work with EV3, and has anyone had experience using ...
3
votes
3answers
989 views

My Blocks with return parameter

I have the retail EV3 kit and have created a function with in and out numeric parameters. While using the [in] params seem quite straight forward, it seems that I can only set the [out] param once. ...
4
votes
3answers
381 views

Holonomic robots using Mindstorms

I just got some Rotacaster wheels and want to try building a 3 wheeled Mindstorms omnibot (holonomic robot) and I'm looking for a practical (easy) discussion about writing a driving program. I've ...
3
votes
1answer
560 views

Can EV3-G MyBlocks be recursive?

Imagine I create a MyBlock called "function1" from a line of blocks. Can I call that block from within itself? This is the program for the block "recursiveTest." Will this block function properly? ...
4
votes
3answers
2k views

API for Android or iOS connecting to EV3 by bluetooth

There is official API for Windows, WindowsPhone8 and WinRT https://legoev3.codeplex.com/ it lets you connect to EV3 brick and control it remotely from your WindowsPhone. Are there any libraries ...
3
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3answers
2k views

EV3 Brick Error Symbols?

I am currently developing an EV3 robot that sorts colored technic beams. However, the brick will only run part of the program and then generate a strange error code on the brick's screen. The error ...
2
votes
1answer
650 views

EV3 Block problems?

I don't see what is wrong with the way i made my program. It looks like this. The idea is that in the while loop [01] shall the robot move forward until it see something brown. If it see ...