I'm trying to read data from the Yost Labs 3-Space Sensor Nano into LabVIEW via an NI MyRIO (1900). I was able to set up a sequence that communicates with the sensor through SPI. However, every time I run the program, it just spits out a single value of 255.
I think understand that I need to include something that allows all the bytes to be read. I just don't know how to go about it.
As an example, I'm trying to read the gyros (0x26) which have a return length of 12 and is a vector (float x3).
Here is my labview code
and here is the manual for the sensor. The commands I'm using are on pages 29-33. In the image, 0x2B is 'read temperature'.
Any help would be greatly appreciated! Thanks :)
Edit: i had messed up the wiring so now the output jumps between ~35 to 255. I'm still having trouble getting all 3 gyro values from the SPI read.
Quoting from Joe Friedrichsen in his comment:
The express block that resets the sensor is not guaranteed to precede the loop because there is no data flow between them. The LabVIEW runtime can see two independent and parallel groups and may choose to execute them simultaneously (which on the wire might mean reset comes between loop commands) or in "reverse" order. Add a wire from reset block to create a terminal on the loop.
Here's a picture of the fix.
You may wish to consider stringing the error wire through your program and wiring it to the stop terminal of the While Loop. Currently, your loop will keep running even if there's a fault in your hardware. Using the error wire would eliminate the need for the flat sequence structure.
I have Pari/GP 32-bit and would like to implement any type of code which runs for a limited amount of time, then automatically stops if nothing is produced by that time. Here is a pseudocode example:
command
...
run command
if run time over 3 minutes
automatically interrupt the program and stop running
I know there is a basic way to do this, I just never found it in the PARI/GP guide. Any help? Thanks.
alarm(5);for(i=1,10^10,continue)
I have a shell script which runs very large simulation binaries. This becomes problematic when I want to request some output of variables in the script. For instance, when I run 10 large simulations, I want to be able to print which iteration I am on without having to wait a minute or two for the current simulation to terminate.
Currently, I am using the trap command. However, the script does not react immediately to signals but will only execute the binded function when the current iteration terminates. I will post the code if anyone needs it.
You should start threads for each large thing you're going to run. Have those threads dump results somewhere, then you have your main method free waiting to interrogate the results on the fly.
I want to check/improve some correction algorithm I use.
The whole thing is implemented in Matlab and goes something like this
for ii = 1:nn
... % Prepare some input files
parfor i = 1:n
system('...'); % simulation code
end
... % Use the output and prepare some stuff that can be used to prep the next iteration
end
Wherey n is a bigger number than the #Treads I can use. This normaly takes a while to run and in the meantime I would like to use the computer for other (non cpu hungry) tasks. Therefore I would like to run the system calls with low priority.
I already tried to do this using new or start but then the call doesn't wait till it's finished and just proceeds. There would be a dirty hack over checking if the output files exist, but then again I was asking myself if there was not a better solution for that...
Any help would be greatly appreciated
yours
magu_
try using the /wait flag in start command:
>> system( 'start /LOW /WAIT matlab.exe' );
started a new matlab instance and resumed execution only after I closed the opened application.
Of course, you need to replace matlab.exe in my proposed solution with the simulation program name you want to run.
This question already has an answer here:
How to abort a running program in MATLAB?
(1 answer)
Closed 7 years ago.
I write a long running script in Matlab, e.g.
tic;
d = rand(5000);
[a,b,c] = svd(d);
toc;
It seems running forever. Becasue I press F5 in the editor window. So I cannot press C-Break to stop in the Matlab console.
I just want to know how to stop the script. I am current use Task Manager to kill Matlab, which is really silly.
Thanks.
Matlab help says this-
For M-files that run a long time, or that call built-ins or MEX-files that run a long time, Ctrl+C does not always effectively stop execution. Typically, this happens on Microsoft Windows platforms rather than UNIX[1] platforms. If you experience this problem, you can help MATLAB break execution by including a drawnow, pause, or getframe function in your M-file, for example, within a large loop. Note that Ctrl+C might be less responsive if you started MATLAB with the -nodesktop option.
So I don't think any option exist. This happens with many matlab functions that are complex. Either we have to wait or don't use them!.
If ctrl+c doesn't respond right away because your script is too long/complex, hold it.
The break command doesn't run when matlab is executing some of its deeper scripts, and either it won't log a ctrl sequence in the buffer, or it clears the buffer just before or just after it completes those pieces of code. In either case, when matlab returns to execute more of your script, it will recognize that you are holding ctrl+c and terminate.
For longer running programs, I usually try to find a good place to provide a status update and I always accompany that with some measure of time using tic and toc. Depending on what I am doing, I might use run time, segment time, some kind of average, etc...
For really long running programs, I found this to be exceptionally useful
http://www.mathworks.com/matlabcentral/fileexchange/16649-send-text-message-to-cell-phone/content/send_text_message.m
but it looks like they have some newer functions for this too.
MATLAB doesn't respond to Ctrl-C while executing a mex implemented function such as svd. Also when MATLAB is allocating big chunk of memory it doesn't respond. A good practice is to always run your functions for small amount of data, and when all test passes run it for actual scale. When time is an issue, you would want to analyze how much time each segment of code runs as well as their rough time complexity.
Consider having multiple matlab sessions. Keep the main session window (the pretty one with all the colours, file manager, command history, workspace, editor etc.) for running stuff that you know will terminate.
Stuff that you are experimenting with, say you are messing with ode suite and you get lots of warnings: matrix singular, because you altered some parameter and didn't predict what would happen, run in a separate session:
dos('matlab -automation -r &')
You can kill that without having to restart the whole of Matlab.
One solution I adopted--for use with java code, but the concept is the same with mexFunctions, just messier--is to return a FutureValue and then loop while FutureValue.finished() or whatever returns true. The actual code executes in another thread/process. Wrapping a try,catch around that and a FutureValue.cancel() in the catch block works for me.
In the case of mex functions, you will need to return somesort of pointer (as an int) that points to a struct/object that has all the data you need (native thread handler, bool for complete etc). In the case of a built in mexFunction, your mexFunction will most likely need to call that mexFunction in the separate thread. Mex functions are just DLLs/shared objects after all.
PseudoCode
FV = mexLongProcessInAnotherThread();
try
while ~mexIsDone(FV);
java.lang.Thread.sleep(100); %pause has a memory leak
drawnow; %allow stdout/err from mex to display in command window
end
catch
mexCancel(FV);
end
Since you mentioned Task Manager, I'll guess you're using Windows. Assuming you're running your script within the editor, if you aren't opposed to quitting the editor at the same time as quitting the running program, the keyboard shortcut to end a process is:
Alt + F4
(By which I mean press the 'Alt' and 'F4' keys on your keyboard simultaneously.)
Alternatively, as mentioned in other answers,
Ctrl + C
should also work, but will not quit the editor.
if you are running your matlab on linux, you can terminate the matlab by command in linux consule.
first you should find the PID number of matlab by this code:
top
then you can use this code to kill matlab:
kill
example:
kill 58056
To add on:
you can insert a time check within a loop with intensive or possible deadlock, ie.
:
section_toc_conditionalBreakOff;
:
where within this section
if (toc > timeRequiredToBreakOff) % time conditional break off
return;
% other options may be:
% 1. display intermediate values with pause;
% 2. exit; % in some cases, extreme : kill/ quit matlab
end