I am trying to compile a Matlab function to C.
Here you have the declaration of the function:
function [SpdLmt0, SpdLmt1, SpdLmt2, SpdLmt3, SpdLmt4, SpdLmt5, SpdLmt6,
SpdLmt7, SpdLmt8, SpdLmt9, SLDst0, SLDst1, SLDst2, SLDst3, SLDst4,
SLDst5, SLDst6, SLDst7, SLDst8, SLDst9, IntTyp1, IntTyp2,
IntTyp3, IntTyp4, IntTyp5, IntTyp6, IntTyp7, IntTyp8, IntTyp9,
IntTyp10, IntDst1, IntDst2, IntDst3, IntDst4, IntDst5, IntDst6,
IntDst7, IntDst8, IntDst9, IntDst10, StpDst1, StpDst2, StpDst3,
StpDst4, StpDst5, StpDst6, StpDst7, StpDst8, StpDst9, StpDst10,
BumpDst1,BumpDst2,BumpDst3,BumpDst4,BumpDst5,BumpDst6,BumpDst7,
BumpDst8,BumpDst9,BumpDst10,SlopeVal1,SlopeVal2,SlopeVal3,SlopeVal4,
SlopeVal5,SlopeVal6,SlopeVal7,SlopeVal8,SlopeVal9,SlopeVal10,
SlopeDst1,SlopeDst2,SlopeDst3,SlopeDst4,SlopeDst5,SlopeDst6,
SlopeDst7,SlopeDst8,SlopeDst9,SlopeDst10,Radius1,Radius2,Radius3,
Radius4,Radius5,Radius6,Radius7,Radius8,Radius9,Radius10,CurvDst1,
CurvDst2,CurvDst3,CurvDst4,CurvDst5,CurvDst6,CurvDst7,CurvDst8,
CurvDst9,CurvDst10,UDP_error] = parser(UDP, longitud)
So I receive UDP data from a "UDP Receive" Simulink block for LINUX. The received message is composed by 100 data (the outputs of the function) codified in ASCII Code. My function "parser" takes the UDP message and decodifies it to have the desired outputs.
The problem is when I try to compile it with the Simulink Coder I have this message:
Error: Errors occurred - aborting
Someone can help?
Without more information about the function, it's hard to know exactly what might be happening, but one recommendation is that you adjust the function call itself a bit. With that many return values, it's entirely possible that MATLAB Coder encountered an error in converting the function. It's pretty unusual to have that many return values, and it may cause problems.
I would suggest putting your return values into a single data structure (a struct or an array depending on what is appropriate). This would simplify your function call and perhaps help Coder out.
Related
My issue involves using the RS-232 Simulink RT blocks.
A model is uploaded to the target PC (xPC) and it transmits and receives data from a variable frequency drive (VFD) that controls a motor. The issue arises on the receiving end when I take data and try to send that data to a display block in my model as a string. Code would be helpful here:
disp = uint8(zeros(1,24));
display = uint8(zeros(1,length(disp)));
cmd = 0;
status = stat_lb;
%% Start-Up
% Initialization Period
if (status == 0 || status == 1)
cmd = 0;
msg = uint8('Start up');
display = [msg uint8(zeros( 1, length(disp)- length(msg) ))];
end
...
%Multiple status cases with unique displays.
...
disp = display
So, here the cmd portion functions as expected. As noted above, I want to display the display string on a display block in my Simulink model. As you can see, though, it is of type uint8, so I need to convert it to type string; however, when I pass it through either the ascii2str Simulink block or just place it in the function call (e.g. display = ascii2str(display)) I get the following error message:
Executing the 'CheckData' command produced the following error: Invalid parameter/value pair arguments
My thought is that this has something to do with the fact that I am using MEX and this function (ascii2str) is not supported. Anyways, I am wondering if anyone knows why I receive this error and if there is anything I can do to resolve it.
Oh, and one last thing: I can get the display to work if I just remove the ascii2str; however, the only problem with this is that the display is in uint8 form and not really helpful. So, if there is any other way that I can decode the uint8 to a string I am all ears.
Thanks!
I have found that there is no support for this feature in Simulink RT. One option is to use external functions, but I found it better for my application to simply output a number and have a table in the simulation that explained what each number meant.
I'm trying to retrieve the serial number from a drive using the MC_BR_GetHardwareInfo function block. Since the documentation lacks any kind of example code on this topic I'm getting nowhere.
Which information should I provide to the function block in order to get the desired serial number?
Below sample will crash in the PLC, probably because the function block requires certain pointers to be addressed:
MC_HARDWARE_INFO_REF hwinfo;
MC_BR_GetHardwareInfo(&hwinfo);
You are probably getting a page fault, because you provide the MC_BR_GetHardwareInfo function block (FUB) a wrong type, which leads to random behavior.
A function block is basically a function which requires a reference to a specific type as parameter. This type contains the actual in- and outputs which are used, internal state variables, etc. We need this, because of the synchronous execution of the code. This means unlike a function, you need to call a FUB until it is done.
Let's take a look to the help of the FUB:
Guid: 056444ea-2a15-4af6-a5ae-0675894b17d3
So the FUB needs a reference to the Axis object of which you want to know the HW info and an Execute command. It will give you some status bits, an error code and the actual data you want to have within the structure HardwareInfo of the type MC_HARDWARE_INFO_REF.
First we need to instantiate the FUB by create a variable of its type. We do this in the local *.var file of the task:
VAR
fbGetHwInfo : MC_BR_GetHardwareInfo := (0);
END_VAR
Then we call set the parameters of the FUB and call it, which might look like this:
void _CYCLIC ProgramCyclic(void)
{
//should be set by the application or in watch/monitor; now it only
//executes once
fbGetHwInfo.Execute = 1;
//reference to your axis object; when using a wizard the first axis
//will be gAxis01 on default
fbGetHwInfo.Axis = (UDINT)&gAxis01;
//call the FUB
MC_BR_GetHardwareInfo(&fbGetHwInfo);
if(fbGetHwInfo.Error == 1)
{
//TODO: errorhandling
}
else if(fbGetHwInfo.Done == 1)
{
//TODO use output
//fbGetHwInfo.HardwareInfo
}
}
typically you would do this in some statemachine. Also you probably have to wait until the network to the drive is initialized. You could check this with the MC_BR_ReadDriveStatus FUB. Just for testing it should be enough to wait for some seconds after reboot and set the Execute flag in monitor mode.
I asked today a question about Parallel Computing with Matlab-Simulink. Since my earlier question is a bit messy and there are a lot of things in the code which doesnt really belong to the problem.
My problem is
I want to simulate something in a parfor-Loop, while my Simulink-Simulation uses the "From Workspace" block to integrate the needed Data from the workspace into the simulation. For some reason it doesnt work.
My code looks as follows:
load DemoData
path = pwd;
apool = gcp('nocreate');
if isempty(apool)
apool = parpool('local');
end
parfor k = 1 : 2
load_system(strcat(path,'\DemoMDL'))
set_param('DemoMDL/Mask', 'DataInput', 'DemoData')
SimOut(k) = sim('DemoMDL')
end
delete(apool);
My simulation looks as follows
The DemoData-File is just a zeros(100,20)-Matrix. It's an example for Data.
Now if I simulate the Script following error message occures:
Errors
Error using DemoScript (line 9)
Error evaluating parameter 'DataInput' in 'DemoMDL/Mask'
Caused by:
Error using parallel_function>make_general_channel/channel_general (line 907)
Error evaluating parameter 'DataInput' in 'DemoMDL/Mask'
Error using parallel_function>make_general_channel/channel_general (line 907)
Undefined function or variable 'DemoData'.
Now do you have an idea why this happens??
The strange thing is, that if I try to acces the 'DemoData' inside the parfor-Loop it works. For excample with that code:
load DemoData
path = pwd;
apool = gcp('nocreate');
if isempty(apool)
apool = parpool('local');
end
parfor k = 1 : 2
load_system(strcat(path,'\DemoMDL'))
set_param('DemoMDL/Mask', 'DataInput', 'DemoData')
fprintf(num2str(DemoData))
end
delete(apool);
Thats my output without simulating and displaying the Data
'>>'DemoScript
00000000000000000 .....
Thanks a lot. That's the original question with a lot more (unnecessary) details:
EarlierQuestion
I suspect the issue is that when MATLAB is pre-processing the parfor loop to determine what variables need to be passed to the workers it does not know what DemoData is. In your first example it's just a string, so no data gets sent over. In your second example it explicitly knows about the variable and hence does pass it over.
You could try either using the Model Workspace, or perhaps just inserting the line
DemoData = DemoData;
in the parfor loop code.
Your error is because workers did not have access to DemoData in the client workspace.
When running parallel simulations with Simulink it would be easier to manage data from workspace if you move them to model workspace. Then each worker can access this data from its model workspace. You can load a MAT file or write MATLAB code to initialize data in model workspace. You can access model workspace using the Simulink model menu View->Model Explorer->Model Workspace.
Also see documentation at http://www.mathworks.com/help/simulink/ug/running-parallel-simulations.html that talks about "Resolving workspace access issues".
You can also move the line
load DemoData
to within the parfor loop. Doing this, you assure that the data will be available in each worker base workspace, wich is accessible to the model, instead of the client workspace.
I am trying to send images from a matlab server to a java client through a sockets. First I converted the image to a byte array and I used the readFully method on the client side which requires a length to be specified.
The problem is that the size of the byte array changes from one image to the other and when I send the size through the write () method it does not read correctly on the client side.
Here is a snippet of my code
Matlab server
%% convert image
Javaimage=im2java2d (image);
Arraystream=ByteArrayOutputStream;
ImageIO.write (javaimage,'jpg', arraystream)
Arraystream.flush ();
Bytearray=arraystream.toByteArray;
%% send size through output stream
Outstream=write (size (byteArray, 1))
%% send array
outStream=write (byteArray);
On the client side I have tried many methods such as read, readInt, readDouble, but I think the trouble is the write () method I tried to use writeInt () but matlab did not recognize it even though I included the libraries needed:
Java.io
Java.net
Java.io.dataoutputstream
Java.io.datainputstream
I should also include that the size of the array is usually over 10000
I would appreciate any help
Thank you in advance
I have finally found the answer which is so simple that it was the last thing to check.
When I created the socket input and output streams I did the following
InStream =socket.getInputStream;
OutStream=socket.getOutputStream;
This allows you to use the methods from the inputStream class such as read () and write() which are methods that only read bytes.To read any other types of data we must use the dataInputStream and dataOutput stream classes which are a type of filter class that allow reading primitive types such as int , double , etc using methods such as readInt () and writeInt
To do this you need to change the above as follows
Instream=dataInputStream (socket.getInputStream);
OutStream=dataOutputStream (socket.getOutputStream);
And its that simple.
I have just recently started to use MATLAB to acquire data off of a data acquisition board and was in need of a function to acquire data continuously (i.e. until I ctrl^C out of the function). To do this I am using the data acquisition toolbox on a 32-bit windows OS.
Based on the documentation in matlab help and a few of the answers on this site, I found that after adding channels to my input handle I should:
set my 'SamplesPerTrigger' to Inf
set the 'TimerPeriod' to some value to trigger the 'TimerFcn'
set the 'TimerFcn' to some subfunction callback which appends data to a persistent variable
Is this a correct way to do this?
My code is as follows:
function acquire_arena_test(samprate,daq_device ,device_ID ,channels, saveroot)
setup.SampleRate = samprate;
setup.DAQdevice = {daq_device, device_ID};
setup.AIChannels = channels;
setup.SaveRoot = {saveroot};
ai = analoginput(setup.DAQdevice{1},setup.DAQdevice{2});
addchannel(ai,[setup.AIChannels]);
set(ai,'SamplesPerTrigger',Inf);
set(ai,'TimerPeriod',0.5);
set(ai,'TimerFcn',{#AcquireData,ai});
start(ai);
while(strcmpi(get(ai,'Running'),'On'))
pause(1)
end
stop(ai);
time = datestr(now,30);
save([saveroot time], 'data');
delete(ai);
clear ai;
function AcquireData(hObject, ~)
persistent totalData;
data = getdata(hObject);
if isempty(totalData)
totalData =data;
else
totalData = [totalData; data];
end
The initial analog input is definitely working properly. I have tried many permutations of giving the AcquireData callback to 'TimerFcn'. The error I receive is
`??? Error using ==> acquire_arena_test>AcquireData
Too many input arguments.
Warning: The TimerFcn callback is being disabled.
To enable the callback, set the TimerFcn property. `
Thanks in advance for any help.
I think the syntax you use for setting up your TimerFcn is wrong. You write
set(ai,'TimerFcn',{#AcquireData,ai});
but this means that your function AcquireData will be called with tree parameters: AcquireData(ai, event, ai) as explained here, which then of course triggers the error message since your AcquireData function only accepts two parameters. Just change your code to
set(ai,'TimerFcn',#AcquireData);
and it should work; the ai object is automatically passed as the first parameter (see the link to the MATLAB documentation above).
Sorry about answering my own question, but I figured it out. The trigger was not needed after all. Using a national instruments board (or a sound card, as it turns out) you can just change the LoggingMode to 'disk' and specify a file to save the .daq (data acquisition toolbox) file to save as with LogFileName. If you want to use the memory on your board, change the mode to disk&Memory. Helpful document:
http://www.mathworks.com/help/toolbox/daq/f12-16658.html
The script below acquires data during the pause, which is as long as you want it to be..
daqreset;
clear all;
ai = analoginput('nidaq','Dev1');
chans = addchannel(ai,0:6);
set(ai,'SamplesPerTrigger',Inf);
set(ai,'SampleRate',1000)
set(ai,'LogToDiskMode','Overwrite')
set(ai,'LogFileName','log.daq')
set(ai,'LoggingMode', 'disk')
start(ai)
pause()
stop(ai)
data = daqread('log.daq');
delete(ai);
Note that you still need to set 'SamplesPerTrigger' to Inf for this to work properly. Thank you to Jonas for his help as well.