Skip to main content

interoperability - Problem with SerialIO package and Lego NXT


I'm following a guide from The Mathematica Journal that describes how to use Mathematica with the Lego Mindstorms NXT but have some trouble getting started and got stuck with the SerialIO package.


I use Mac OSX and I have installed the package to:



/Applications/Mathematica.app/AddOns/ExtraPackages/SerialIO/

The command Needs["SerialIO`"] gives me the following error message:


LinkOpen::linke: Could not find MathLink executable.

And trying


SetDirectory[FileNameJoin[{$InstallationDirectory, "AddOns", "ExtraPackages", "SerialIO", $SystemID}]];

Does not help either, it gives:


SetDirectory::cdir: Cannot set current directory to /Applications/Mathematica.app/AddOns/ExtraPackages/SerialIO/MacOSX-x86-64.


There seem to be some problem with the alias/symbolic link in the SerialIO folder. By default they pointed to an absolute directory on the machine that this library was built on:


MacOSX-x86-64 -> /Files/schofield/Packages/SerialIO/Build/Mac/build/Deployment/Package/SerialIO/MacOSX

I tried deleting the alias and creating a symbolic link in the terminal:


# ln -s MacOSX MacOSX-x86-64

Running the SetDirectory command again result in... no result, so I guess thats good. The commands seem to have been loaded as when typing Serial it want to autocomplete to SerialOpen etc.


However, using the command mybrick = SerialOpen["NXT"] does not put the NXT in connected mode (<> on NXT display). Does anyone else got it to work?



Answer




I finally got it to work with a little help of this and a git hub repo of the SerialIO package.


The problem was the line $Link = Install["SerialIO"] in init.m. This seem to only be valid on Windows so I changed this to the suggested $Link = Install["SerialIO", LinkProtocol->"Pipes"] and it now works.


Also, the mybrick = SerialOpen["/dev/tty.NXT"] had to include the full path to the serial port.


OSX aliases did not work either. I had to create a symbolic link alternatively create a "MacOSX-x86-64" folder with the SerialIO application to make it work.


Comments

Post a Comment

Popular posts from this blog

list manipulation - Selecting multiple columns from a matrix?

Sample data: data = { {{2013, 1, 1}, 24.13, 167.67, 231.82}, {{2013, 1, 2}, 32.15, 170.92, 225.99}, {{2013, 1, 3}, 35.43, 172.68, 221.67}, {{2013, 1, 4}, 36.73, 173.05, 218.32}, {{2013, 1, 5}, 58.19, 165.96, 197.05}, {{2013, 1, 6}, 69.99, 163.50, 187.52}, {{2013, 1, 7}, 71.37, 154.21, 175.58}, {{2013, 1, 8}, 72.51, 149.66, 163.25}}; I want a DateListPlot with three graphs, so for a matrix formed by columns 1 and 2, one for columns 1 and 3, and 1 for columns 1 and 4. At the moment I'm using this code: data2 = Transpose[{data[[All, 1]], data[[All, 2]]}]; data3 = Transpose[{data[[All, 1]], data[[All, 3]]}]; data4 = Transpose[{data[[All, 1]], data[[All, 4]]}]; DateListPlot[{data2, data3, data4}, Joined -> True, Filling -> {3 -> {1}}] but I have a hunch that this can be done more efficiently. I don't like the Transpose s in particular. Any ideas? edit (for extra credit) What if I need to multiply the second column by 2, which in my solution is simp...
Post a Comment
Read more

plotting - How to draw lines between specified dots on ListPlot?

I would like to create a plot where I have unconnected dots and some connected. So far, I have figured out how to draw the dots. My code is the following: ListPlot[{{1, 1}, {2, 2}, {3, 3}, {4, 4}, {1, 4}, {2, 5}, {3, 6}, {4, 7}, {1, 7}, {2, 8}, {3, 9}, {4, 10}, {1, 10}, {2, 11}, {3, 12}, {4,13}, {2.5, 7}}, Ticks -> {{1, 2, 3, 4}, None}, AxesStyle -> Thin, TicksStyle -> Directive[Black, Bold, 12], Mesh -> Full] I have thought using ListLinePlot command, but I don't know how to specify to the command to draw only selected lines between the dots. Do have any suggestions/hints on how to do that? Thank you. Answer One possibility would be to use Epilog with Line : ListPlot[ {{1, 1}, {2, 2}, {3, 3}, {4, 4}, {1, 4}, {2, 5}, {3, 6}, {4, 7}, {1, 7}, {2, 8}, {3, 9}, {4, 10}, {1, 10}, {2, 11}, {3, 12}, {4, 13}, {2.5, 7}}, Ticks -> {{1, 2, 3, 4}, None}, AxesStyle -> Thin, TicksStyle -> Directive[Black, Bold, 12], Mesh -> Full, Epilog -> { Line[ ...
Post a Comment
Read more

dynamic - How can I make a clickable ArrayPlot that returns input?

I would like to create a dynamic ArrayPlot so that the rectangles, when clicked, provide the input. Can I use ArrayPlot for this? Or is there something else I should have to use? Answer ArrayPlot is much more than just a simple array like Grid : it represents a ranged 2D dataset, and its visualization can be finetuned by options like DataReversed and DataRange . These features make it quite complicated to reproduce the same layout and order with Grid . Here I offer AnnotatedArrayPlot which comes in handy when your dataset is more than just a flat 2D array. The dynamic interface allows highlighting individual cells and possibly interacting with them. AnnotatedArrayPlot works the same way as ArrayPlot and accepts the same options plus Enabled , HighlightCoordinates , HighlightStyle and HighlightElementFunction . data = {{Missing["HasSomeMoreData"], GrayLevel[ 1], {RGBColor[0, 1, 1], RGBColor[0, 0, 1], GrayLevel[1]}, RGBColor[0, 1, 0]}, {GrayLevel[0], GrayLevel...
Post a Comment
Read more