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5

The NXT actually uses IEEE 794 32-bit floating point number format in little endian byte order. I like using this site for conversions. So, to decode your messages: TX: 00 09 00 05 60 EA 00 00 00 Byte 0: 0x00 - response required Byte 1: 0x09 - write message command Byte 2: 0x00 - Mailbox 1 Byte 3: 0x05 - Message size of 5 bytes Bytes 4-7: 0x60 ...


4

The most basic solution would be to store the character read by fgetc, for example, instead of: if(!isspace(fgetc(handle))) you'd write: char val = fgetc(handle); if(!isspace(val)) This way if the isspacecall returns false you will still have the latest character in the val variable. I'd also suggest you look into the switch statement instead of using ...


3

There is a tool called NeXTScreen that is available here that will let you see the screen (and remotely control the NXT). There are similar tools for OS X and Linux on the same page. Once you have this setup, you should be able to use any programming environment that you like. The screen viewing programs should be able to run at the same time as anything ...


3

Yes, it is possible. Have a look at the "Comm module functions" section of the NXT help file. For example, since the touch sensor status is a boolean value, you could use the SendRemoteBool and ReceiveRemoteBool functions. You can communicate wirelessly using the Bluetooth functions (BT*) or you can have a wired connection using RS485 by connecting input ...


3

You probably don't need it, but the LEGO Education NXT 2.1 Software is still for sale through LEGO Education (at least in the USA). They do not advertise and upgrade price, but it does not hurt to ask. The Energy Meter blocks are available for download on the LEGO Education website. I went to http://education.lego.com/en-us/downloads and checked the box ...


2

It could be that one wheel slips more than the other. This happens when the tires get dirty. Also, you can adjust your center of balance so that more weight is on the drive wheels and they will slip less. You can also use the gyro sensor to compensate for any slippage of the wheels.


2

Not sure what language you are using, or calls you are making before this, but: float var_Min = var_R; if (var_G > var_Min) var_Min = var_G; if (var_B > var_Min) var_Min = var_B; Should be (note the use of < rather than >) float var_Min = var_R; if (var_G < var_Min) var_Min = var_G; if (var_B < var_Min) var_Min = var_B; Your posted code ...


2

PosRegSetAngle should set the position of the motor relative to the position the motor was in when regulation was enabled. In what way didn't it work when you tried this? It sounds like you may be asking how to wait for the rotation to finish. I'm not sure if there is a built-in way to do this in NXC or not, but I think that something along these lines ...


2

That's not possible - sensor ports don't have the hardware to drive motors. That said, you can buy a motor multiplexer like this one to do the job for you, if competition rules allow this.


2

https://bitbucket.org/Thad_Hughes/cortex/src Here's something in NXC and python that routes from NXT1 to NXT2 through the PC; emulating a non-master/slave config between all three devices. Has the added benefit of a seamless pairing method. It could be helpful to give a little more detail (what languages you are using, what direction(s) of communication ...


2

The adapter itself is generally called a "Molex" adapter. The one you have pictured looks similar to their Mini-Latch style. I would recommend an adapter like this. The pin spacing should be the same even if it is not made specifically for that connector. The red wire connects to pin 1 and the black wire connects to pin 2. The yellow wire is for speed ...


2

There is a modified Color sensor block available here. As of this writing, this is the most up-to-date direct link to download the block.


2

I had that error when trying to install the NXT 2 installer (after having previously uninstalled Flash, to be sure). What I did was to not run the main installer, but instead the language specific installer (in my case English ... .mpkg, if I am not mistaken). I am not sure if I just used a different download for EV3 or if I just automatically skipped the ...


2

I have had the sound go out on one or two NXTs. I was able to restore it by doing a factory reset. On the back of the NXT, there are 12 technic pin holes. In the one closest to USB port, you will see a metallic button. With everything unplugged from the NXT and with the NXT powered on, press the button with a paper clip or other instrument that will fit in ...


1

One approach could be to install each parts manually: -go to th 'Parts' Folder in MINDSTORMS NXT (^^^^^) -Uninstall Flash Player if you don't have Flash Player 10 -Install Flash Player 10 from the 'PARTS' folder -Install the packages in the language you prefer -Install the packages that have no specified language -Go to launchpad and click MINDSTORMS ...


1

I know this is 3 and a half years late, but I figured I'd throw in my two cents. Attach an NXT light sensor and an RCX light sensor facing into each other. You can communicate bi-directionally by flashing the built-in LEDs. On the RCX side, this can be accomplished by switching the sensor mode between touch sensor and light sensor to passivate or ...


1

I recently did some testing to get the EV3 software working on Linux using Wine, and actually got it to work! (The EV3 software can also be used to program the NXT) Here are the instructions: $ sudo add-apt-repository ppa:wine/wine-builds $ sudo apt-get install --install-recommends winehq-devel winbind libntlm0 ttf-mscorefonts-installer winetricks Make ...


1

The error was caused because the file rw.txt was not uploaded to the nxt performing: t2n -v -put rw.txt Solved the problem.


1

There is a great video on YouTube that shows how to repair this. https://www.youtube.com/watch?v=eCZNc7tPop0 Basically, there are some surface mount capacitors on the PCB board for the screen/buttons that need a little bit of soldering to make sure they are properly electrically connected. I have performed this repair myself with success.


1

A speed in second makes no sense to me. Are there more information about this motor, like to maximum rpm/power ? If so, maybe that the scale from -100 to 100 is some sort of percentage of max rpm/power, with the positives being one rotation direction and the negatives the other ?


1

Most probably the problem is that the array is declared, but not initialized. The program does not know how much memory to allocate for this specific array and so there is no allocated storage in RAM for this array. To solve this, try initializing your array. You can either provide the starting dimensions during declaration, like in the last example here: ...


1

Since you are trying to solve a Rubik's cube, check out the source code for the MindCuber. The solution there is that the values are not actually converted into colors. Rather the raw values are converted to HSV and then sorted by hue. The actual value does not matter, just how close it is to the other values. The Mindcuber also has a white calibration. ...


1

You can use any programming language you like to remotely control the NXT provided that it can access a serial port of your computer. The Bluetooth connection on the NXT provides a virtual serial port. You can see this by opening "Devices and Printers" and double-clicking on the NXT (provided that you have already paired it). Then have a look at the ...


1

You have a number of options. Since you mentioned you know C# the best, have a look at http://monobrick.dk. They have a C# library that lets you remote control the NXT. Then you could use something like http://playground.arduino.cc/Interfacing/Csharp to do the same for the Arduino. For Java, there is a similar NXT remote control library from ...


1

I managed to install my license of Mindstorms Edu NXT v2.0 (Windows 7 x64) and the software has Data Logging and the Temperature Sensor Block. If you have an upgrade from v1.0 to v2.0 at least the Temperature Sensor Block will be available.


1

Yes it is possible. You just need to write a program for NXT1 that forwards the messages from the PC to NXT2.


1

Control loops. The builtin RotateMotor commands are very imprecise. Have a look at this file for a nice library that makes skid steer vehicles turn very precisely: https://www.dropbox.com/s/o31qaxx0glx4m3x/Instacode.h?dl=0 You'll need to adjust the constants at the top of the file.



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